Borderlands 2 pop culture references

Alice's Adventures In Wonderland

 * Sanctuary Hole's challenge "Down the Rabbit Hole" is a reference to the famous novel Alice's Adventures in Wonderland.

Beowulf

 * In Captain Scarlett and Her Pirate's Booty, Sir Hammerlock offers a mission to kill a bullymong named Grendel, a reference to the monster of the same name in the epic poem Beowulf.

Bright Lights, Big City

 * The name of the mission "Bright Lights, Flying City" is a reference to the book of a similar name by author Jay McInerney.

DC Comics

 * The Siren's "Blackest Night" skin is a reference to an oath from a DC Comics hero Green Lantern. It is also a reference to DC's cross-over event, "Blackest Night."
 * The Assassin's "Blue Scarab" skin is a reference to the DC character Blue Beetle.
 * The Gunzerker's "Woe-In-The-Dark" skin is a reference to the DC character Joker.
 * There is a boss character named Rakkman, referencing DC's hero, Batman.

Gone with the Wind

 * The challenge "Gone with the Second Wind" is a play on the novel Gone with the Wind.

Green Hornet Comics

 * The Siren's "Emerald Hornet" and "Fright of the Bumblebee" skins are references to Green Hornet Comics comic books, specifically the protagonist's sidekick.

Hamlet

 * Occasionally, a psycho will recite the entire "Too solid flesh" soliloquy from poet William Shakespeare's Hamlet.
 * Upon dying, goliaths may say "Goodnight, sweet prince," a quote from Hamlet.
 * The Hyperion New-U station will sometimes say: "Welcome back from your visit to the undiscovered country," a reference to the extremely well known "To be, or not to be" soliloquy from Hamlet.

If You Give a Mouse a Cookie

 * In Lynchwood, there are a series of missions that are references to the children's picture novel If You Give a Mouse a Cookie.

The Hitchhiker's Guide to the Galaxy

 * Sometimes, when an enemy's weak spot is highlighted with the Assassin's B0re skill, the text near the highlighted area says "42," which is "The Answer to the Ultimate Question of Life, the Universe, and Everything" in the famous novel franchise The Hitchhiker's Guide to the Galaxy.
 * The Action Skills of the Commando and Gunzerker have a base cooldown of forty-two seconds, another reference to The Hitchhiker's Guide to the Galaxy.
 * When beginning the fight with BNK-3R some ones and zeros are be displayed on his title card. These numbers are the binary code for 42.
 * In the second Lost ECHO recording detailing Zer0's backstory, Handsome Jack tells Angel she's "got a brain the size of a planet," which is a reference to Marvin the depressed android's "brain the size of a planet" lament.

The Iceman Cometh

 * The mission "The Ice Man Cometh" is a reference to the Eugene O'Neill's 1939 play The Iceman Cometh.

Logan's Run

 * The name and red flavor text of the legendary pistol, "Logan's Gun" are references to the 1967 novel by William F. Nolan and George Clayton Johnson, Logan's Run.

The Lord of the Rings

 * In a mission in Eridium Blight, one must bring "Geary's Unbreakable Gear" to Geary on the top of a volcano; all a reference to the novel The Return of the King.
 * In Tiny Tina's Assault on Dragon Keep, Claptrap, posing as a wizard, slams his staff into the ground while yelling "You! Shall! Not! Pass!"

Macbeth

 * The mission "Toil and Trouble" is a reference to a line spoken by witches in William Shakespeare's Macbeth.

Marvel Comics

 * The Gunzerker's I'm the Juggernaut Skill is a reference to the Juggernaut character from Marvel Comics; in a humorous parody of the character, he exclaims, "I'm the Juggernaut, bitch," which became a very popular internet meme.
 * The Gunzerker's "Salvador SMASH" skin is a reference to the Marvel Comics character Hulk, known for commonly yelling, "Hulk smash!"
 * Lab Rat 's will sometimes say, "Optic blast!" before shooting lasers from their eyes which is the name of the mutant ability of Cyclops, a member of the X-Men.

The Man With the Golden Gun

 * Axton's "The Man With the Golden Pun" skin is a reference to the twelfth James Bond novel The Man with the Golden Gun.

No Country for Old Men

 * Sometimes in Sanctuary, a Crimson Raider will say, "This is no planet for old men," referencing the novel No Country for Old Men.

The Once and Future King

 * The mission "The Once and Future Slab" is a reference to the supposed epitaph of the legendary King Arthur, which reads, "Here lies Arthur/The Once and Future King."

Paradise Lost

 * The Commando's "Red Right Hand" skin is a reference to a line in John Milton's poem Paradise Lost.

Phantom Tollbooth

 * The challenge "The Not-So-Phantom Tollbooth" references the Norton Juster book The Phantom Tollbooth.

Pinocchio

 * The character Mal and his missions are references to the character Pinnochio from the novel The Adventures of Pinnochio.
 * The Fibber's flavor text refers to Pinocchio's tendency to lie.

Portrait of the Artist as a Young Man

 * The challenge "Portrait of the Gunzerker as a Young Man" is a reference to the Portrait of the Artist as a Young Man novel of the same name.

The Raven

 * The Siren's "Nevermore" head is a references a quote from the Edgar Allan Poe story The Raven.

Romeo and Juliet

 * The Morningstar has red text in its description that reads "a Rose by another name" which is a reference to the lines in William Shakespeare's Romeo and Juliet.

Sam & Max

 * The Mechromancer's "Speak No Evil" head bears a striking resemblance to a character from Sam &amp; Max. Her Hippity Hoppity head, a reward from the game Poker Night 2, is a Max mask.

A Study in Scarlet

 * The mission "A Study in Scarlett" is named after A Study in Scarlet, the first Sherlock Holmes-related novel.

Slaughterhouse 5

 * Sometimes, when the Siren kills an enemy, she will say "So it goes," a phrase used commonly in the novel Slaugherhouse 5.

A Song of Ice and Fire Series

 * Occasionally, a Crimson Raider in Sanctuary will say, "Winter is coming," a reference to the novel series A Song of Ice and Fire.
 * The challenge "Game of Thorns" is a reference to the series' first volume, A Game of Thrones.
 * The Commando, after being revived, will occasionally exclaim "Not today," a famous phrase used in A Game of Thrones.
 * The Commando's "Ice and Fire" skin is an obvious reference to the series.

Snow White and the Seven Dwarves

 * The mission "The Cold Shoulder" involves luring Scooter's cannibalistic love interest Laney White away from her new family of seven midgets. Her new home has seven beds and a double bed for her; all a reference to the novel Snow White and the Seven Dwarves.
 * The challenge "Fairest of Them All" is likewise a reference to Snow White and the Seven Dwarves.
 * The challenge "It's Off to Hell We Go" references the song lyrics sung in the novel, "It's off to work we go."

Twilight

 * The Mechromancer's Make it Sparkle Skill's flavor text says "Robots are like vampires: they sparkle when hit with incendiary rounds," in reference to how the vampires in the Twilight series of novels sparkle in sunlight.

The Dark Tower

 * An announcement in Overlook is occasionally made saying, "Hyperion congratulates Harriet Blavis on the birth of her twins, and wishes her luck in choosing which one to keep." This is a reference to the robotic "wolves" in the The Dark Tower novel series.

xkcd

 * The reward for completing the mission "Hyperion Contract " is a Morningstar sniper rifle that the Hyperion recording describes as the "ex-K Seedy" experimental weapon. This weapon taunts its owner with phrases like, "Great, now you're wasting ammo," or, "Good shot, murderer." This is all a reference to the webcomic xkcd. Issue #873 of kxcd is itself about an FPS reciting morose phrases to the player when they kill someone.

3:10 to Yuma

 * The mission "3:10 to Kaboom" is a reference to the movie 3:10 to Yuma.

Alien vs Predator

 * Zer0’s Alienati0n head is a reference to the Xenomorph/Predator cross-species found in the Alien vs. Predator franchise.

Aliens

 * The title of the challenge "Another Bug Hunt" is a reference to the movie Aliens, when Private Hudson asks "Is this gonna be a standup fight, sir, or another bug hunt?"

Annoying Orange

 * The Gunzerker has a skin titled "Annoying Orange", a reference to the YouTube/Cartoon Network show of the same name.

Apocalypse Now

 * Buzzard pilots will occasionally sing the first phrase of the "Valkyrie" motif from "Der Ring des Nibelungen", an opera by Richard Wagner, alluding to the famous helicopter scene from the movie.
 * A mission in the Captain Scarlett DLC is titled "Smells Like Victory" - taken from the infamous napalm quote from Colonel Killgore.

Arrested Development

 * The news-man in Sanctuary occasionally says, "There's always money in the news stand," an echo of George Bluth Sr.'s reminder to Michael, "There's always money in the banana stand!".
 * There is a Gunzerker skin named, "I Blue Myself" in reference to a line spoken by character Tobias.

Bad Boys

 * The challenge "Ride Together, Die Together" is a segment of the motto of main characters Mike Lowery and Marcus Burnett (played by Will Smith and Martin Lawrence, respectively). "We Ride Together, We Die Together - Bad Boys For Life"
 * Salvador's skill "Just Got Real" may also be a reference Bad Boys 2, when Marcus states "Shit just got real."

Batman

 * There is a location in The Fridge known as the "Rakk Cave." Rakkman inhabits this area and carries similar weaponry to the character Batman.
 * The ECHO recording from the Fridge includes a message from the Rakkman. The Rakkman shouts: "I am throatscratch, I am the pants, I! AM! RAKKMAN!", which is reference to iconic Batman line "I am Vengeance! I am the Night! I! AM! BATMAN!" from the 1992 Batman: The Animated Series.
 * On Playthrough 2, Rakkman is renamed to Rakkman Forever. A reference to the film, Batman Forever.

Big Trouble in Little China

 * Gaige's shock/lightning-focused middle skill tree is called Little Big Trouble, which is partly based on one of the Three Storms warriors, Lightning.

Boondock Saints

 * The red text on the item rewards for completing Clan War: Hodunks vs. Zafords on the Zaford side is "Aequitas" or "Veritas," depending on the item chosen. These words are the tattoos on the McManus brothers' hands in Boondock Saints.

Breaking Bad

 * There is a head for Salvador called "Breaking Bald", which makes Salvador look like the protagonist, Walter White, from Breaking Bad.
 * Occasionally psychos will yell "I am the one who knocks!" while in combat. This is another reference to Breaking Bad. The original line, as delivered by the main character, Walter White, is: "You clearly don't know who you're talking to, so let me clue you in: I am not in danger, Skyler. I am the danger. A guy opens his door and gets shot, and you think that of me? No! I am the one who knocks!"

Captain Scarlet and the Mysterons

 * The pirate boss Captain Scarlett in Captain Scarlett and Her Pirate's Booty is named after the star of Gerry Anderson's 1960s TV series. Like Scarlet himself, she seemingly dies but is later revealed to be alive, though unlike Scarlet she never actually dies.

Chappelle's Show

 * The challenge "Eff Yo' Couch" is a phrase coined by Dave Chappelle during the skit "Charlie Murphy's True Hollywood Stories" where he describes the events that took place when he invited Rick James into his home. During the re-enactment, Dave Chapelle (acting as Rick James) ground his feet into a white couch while shouting the phrase.
 * A Rat Thief upon stealing money from a Vault Hunter will sometimes yell, "I'm rich BIATCH!"

A Clockwork Orange

 * Vladof sniper rifles weapons use Nadsat slang terms in their names such as Droog, Dobby, Britva, Pooshka, Moloko and Horrorshow.

Community

 * NPCs in Sanctuary will sometimes use the phrase "Streets ahead.", coined by Pierce in Community.
 * Gaige has skins called "Streets Ahead", and "Cool Cool Cool". The latter being the catchprase of Abed Nadir.

Cool Hand Luke

 * The challenge "Failure To Communicate" is a reference to the line "What we've got here is failure to communicate." uttered by the prison warden, Captain.

The Crow

 * The "Nevermore" head given to Maya at the end of the mission In Memoriam technically references Edgar Allan Poe's "The Raven," but the makeup the head wears imitates the makeup worn by the main characters in this film series.

Crouching Tiger, Hidden Dragon

 * The challenge "Crouching Tiger, Hidden Assault Rifle" is a reference to the movie title.

CSI: Miami

 * There is a mission in Sanctuary named Won't Get Fooled Again after the theme song licensed for CSI: Miami. In the mission, players are asked to assist Marshall Friedman with a murder investigation. If successful, Friedman will comment on the case with a corny one-liner in the style of CSI: Miami protagonist Horatio Caine

The Dark Knight

 * By looting/buying a certain amount of green-rarity gear, players can unlock a skin for Zer0 called "Why So Serious?" It is green, white, and purple and is a reference to a line delivered by the Joker in the film The Dark Knight.
 * There is a Gunzerker skin called "Woe-In-The-Dark" which is a reference to the Joker's iconic purple and green suit.
 * Rakkman also has an ECHO recorder titled "The Rakk Knight".

Das Boot ( Beerfest )

 * The monitor screens in the Hyperion Wildlife Exploitation Facility indicate a boot sequence named "Das Boot".

The Day The Earth Stood Still

 * Gaige will sometimes yell "klaatu barada nikto" when getting a Deathtrap kill, which is a phrase originating from the 1951 science fiction film The Day the Earth Stood Still.

DeepStar Six

 * The facility "Dahl Deep Core 06," a reference to the 1989 underwater monster movie.

Die Hard

 * Salvador's skill "Yippee Ki Yay" is a reference to the same phrase in Die Hard.

Dirty Harry

 * Salvador's skill "5 Shots Or 6" is a reference to the famous "Do you feel lucky?" monologue.
 * There is a pistol with red text that reads: "Did I fire six shots, or only five? Three? Seven. Whatever." It is a reference to the same monologue above. It is found on the pistol Unkempt Harold which is not only similar to Dirty Harry's .44 Magnum, but bears a name synonymous with the titular character.

Doctor Who

 * A random citizen will sometimes say "I'm missing the new episode of Constable What!", a parody of Doctor Who.
 * After blowing up the dam in "Hell Hath No Fury" Jack will list four names of workers killed in the flooding, all of which are the names of the first four actors playing the Doctor in Doctor Who. These are William Hartnell, Patrick Troughton, Jon Pertwee, and Tom Baker.
 * At the beginning of the game Claptrap says "Allons-y!", which the 10th Doctor from Doctor Who is known to say.
 * The NPCs constantly knocking on walls in Sanctuary seem to be doing so in a similar beat and fashion to the subliminally-controlled humans in the Doctor Who episode "The Sound of Drums." The Master also refers to Captain Jack Harkness as "Handsome Jack" in that episode.
 * ECHOs found in Lynchwood bandits named 'John' and 'Barrowman' reference Doctor Who and Torchwood actor John Barrowman, who played character Jack Harkness.
 * There is a skin for Maya called Rose Tailor, a play on the character Rose Tyler from Doctor Who.
 * In the Bloodshot Ramparts, there is a small platform aside a crane that has a teddy bear with a bow tie and 3-D glasses, which is a possible reference to the series for the 10th Doctor wearing 3-D glasses in an episode, and the 11th Doctor's fondness of bow ties.
 * Hyperion robots can often be heard uttering "Deleted!" which is a popular phrase of the Doctor Who enemy, the Cybermen.
 * In the character selection screen, CL4P-TP sometimes says, "I need to pee," which will trigger him to go into the outhouse. Said outhouse will then vanish, and pop back up, much in the same manner of the Doctor's TARDIS
 * The character Maya was given to the Order of the Impending Storm, a play off of the nickname Oncoming Storm, given to the Doctor by the Daleks.

Don't Copy That Floppy

 * The side mission "Don't Copy That Floppy" in the "Captain Scarlett and Her Pirate's Booty" DLC is likely named after the 1992 anti-copyright infringement video of the same name.

Firefly

 * In Liar's Berg, one of the buildings is named "Fillion's Ammunition & Arms". Nathan Fillion is an actor who was in the show Firefly which had a similar 'space western' setting.

Flash Gordon

 * The combat rifle, Hail, has red text that reads: "What play thing can you offer me today?" This is a reference to the movie Flash Gordon with the line "Klytus, I'm bored. What plaything can you offer me today?"

Full Metal Jacket

 * In the challenges section, "This is My Rifle..." and then "...This is My Gun" were made from the Rifleman's Creed, a Marine Corps maxim, which was used in the film Full Metal Jacket in this fashion.

Full House

 * NPC in the Captain Scarlett DLC is named DJ Tanner. While the character IS a disc jockey, this is also the name of Candice Cameron's character from the show.

G.I Joe

 * Zer0's "Eyes of a Snake" skin is a reference to Snakes Eyes from the G.I Joe series.
 * The achievement "Knowing Is Half The Battle" was a phrase used during the Public Service Announcement segments at the end of the 1980's G.I Joe cartoon show.

Godzilla

 * Dukino's Mother, from the "Demon Hunter" mission, is very similar to Skagzilla from the original Borderlands. In addition, her large shoulder spikes resemble those seen on the adaptation of Godzilla in the 1998 film.

The Good, the Bad, and the Ugly

 * The mission The Good, The Bad, and the Mordecai is a reference to the Clint Eastwood western film The Good, the Bad, and the Ugly. Players also must find an NPC named Carson in Friendship Gulag during the mission, a nod to the character Bill Carson from the film. In addition to hiding the 'treasure' in an unmarked grave, the mission also ends with a 3-way shootout.

The Great Train Robbery

 * The mission "The Pretty Good Train Robbery" is a reference to the 1903 film, The Great Train Robbery.

Homestar Runner

 * When rescued in Liar's Berg, Sir Hammerlock mentions the town was once full of "hustle and/or bustle", a possible reference to Homestar Runner.
 * In Sanctuary, NPC's playing darts in Mad Moxxi's bar will occasionally say "And that's why they call me The Yellow Dart."
 * One of Zer0's skins is also labeled as "The Yellow Dart".

Hunger Games

 * Occasionally when picking up loot from the ground, a Rat Thief will say, "That's mahogany," a reference to Effie Trinket's line, "That is mahogany!"

Indiana Jones and the Kingdom of the Crystal Skull

 * The head "Alienati0n" for Zer0 is a reference to the crystal skulls from the movie.

Iron Chef

 * Rats will often shout "Allez cuisine!" This phrase is used to start the competitions in the Japanese cooking show Iron Chef and its international spinoffs. As rats are cannibals, it makes a fitting battle cry.

It's Always Sunny in Philadelphia

 * Gaige has a skin called It's Always Sunny on Pandora, referencing the TV show It's Always Sunny in Philadelphia.

Joe Versus the Volcano

 * When completing the "Geary Easter Egg, and continuing through the obstacle course, players will reach a Lance Chest, along with completing the challenge "Vault Hunter vs. The Volcano".

Johnny Quest

 * In Tiny Tina's Assault on Dragon Keep, Wizards will sometimes chant "Sim sim salabim." This is a reference to Haji's chant before casting his magic.

King Kong

 * The challenge "'Twas Slag Killed The Beast" is a reference to the ending line of King Kong "'twas beauty killed the beast."
 * There is a giant bullymong in Eridium Blight named "King Mong", an obvious reference to the titular "King Kong".

Kiki's Delivery Service

 * There is a Tediore manufactured shotgun called Deliverance. The name of the gun and the red text which reads "Kiki got a shotgun" is a reference to the movie Kiki's Delivery Service.

Kuffs

 * The Gunzerker skill "No Kill Like Overkill" contains a quote reading "I'm looking for a really big gun that holds a lot of bullets." This is a line spoken by Christian Slater's character in the 1992 film Kuffs.

Law & Order

 * There is a revolver called Law and a shield called Order. Both items benefit from the player equipping both. The red text on Order is "Chung-gunk!" a reference to the "Law & Order sound." Sometimes the sound is referred to "Chung-chung" or Gunk-gunk".

Lethal Weapon 2

 * While gunzerking with Salvador, he can sometimes be heard saying "It's been revoked!", a reference to the line from Lethal Weapon 2.

The Lion King

 * Somewhere in the Wildlife Exploitation Preserve, there is a skag named "Tumbaa" and a stalker named "Pimon". This is a reference to Timon and Pumbaa from the movie The Lion King.

The Little Mermaid

 * Axton's skin, "Unda Da Sea" is a reference to the song sung by Sebastian in the movie.

Mad Max

 * "...One Van Leaves" challenge is a reference to the line "Two men enter, one man leaves." used in the film Mad Max Beyond Thunderdome.

Mad Men

 * There is a skin for Salvador called "Smoke Gets In Your Eyes" which is a reference to the title of the first episode of Mad Men and is also the title of a long-lived show tune.

Major League

 * The special effect text for the Fastball grenade mod, " Forget the curveball Ricky, give him the heater. " is a reference to the line James Gammon's character, Lou Brown, says during the final at bat.

Man on Wire

 * The challenge "Vault Hunter on Wire" is a reference to the documentary film "Man on Wire". This is further indicated by the challenge's goal of using a tightrope as the film is about Philippe Petit, a famous tightrope walker.

Masters of the Universe

 * Axton's "At Arms" skin is a reference to Man at Arms from the cartoon and toy line Masters of the Universe.

The Matrix

 * The Dahlminator's flavor text "Dodge this." is a reference to the famous line in The Matrix.

Men in Black

 * There is an NPC in the Badass Crater Bar who says, "Behind Jack's mask, there is a tiny alien controlling the robot structure that is Handsome Jack." This is a reference to Rosenberg, the Arquillian prince in Men in Black.

Mighty Morphin' Power Rangers

 * The mission "Mighty Morphin'" is a reference the 1990s children's show Mighty Morphin' Power Rangers, the original series from the Power Rangers franchise.

Monty Python and the Holy Grail

 * The special text for Maya's Converge skill "Gather thine enemies together that thou mayest blow them to tiny bits" is a reference to a line spoken by Michael Palin in the 1975 Monty Python movie regarding use of the Holy Hand Grenade of Antioch.
 * The legendary Grenade Mod, the Fire Storm, has the flavor text which is a reference to 'Tim the Enchanter', played by John Cleese.

The Muppets

 * The Challenge "It's Not Easy Looting Green" references Kermit the Frog's song "Bein' Green".

My Little Pony: Friendship is Magic

 * In the credits, a member of the game's production team, Chris Francis, says thanks to "his adorable Fluttershy ", one of the characters from the TV show.
 * All the characters can unlock a costume, the Pink Pandoracorn, which has the same overall color scheme as the one of the main characters, Twilight Sparkle. It also features an image of a unicorn on their body, which is the same type of pony Twilight Sparkle is.
 * It even makes Maya's hair purple with pink stripes, just like Twilight Sparkle's mane and tail.
 * Several of Gaige's skills are references to this show.
 * Her Potent as a Pony skill is a reference to the show itself, though fans have thought it may reference Big MacIntosh, due to him being the strongest pony in Ponyville.
 * Her Buck Up skill is a reference to a line often spoken by many of the characters of the series when cheering someone else up.
 * Her 20% Cooler skill is a reference to a popular quote spoken by Rainbow Dash from the episode "Suited for Success".
 * Her Evil Enchantress skill refers to a song from the episode "Bridle Gossip".
 * It's also a reference for the character Zecora from the same episode.
 * Her Fancy Mathematics skill is a reference to a certain line spoken by Applejack from the episode "Applebuck Season".
 * The skill Sharing is Caring is a reference to a song sung by Pinkie Pie from the episode "Over a Barrel".
 * The skill Discord is a reference to a major villain of the Same Name.
 * Her skill The Stare is a reference to an ability the character Fluttershy uses when dealing with misbehaving animals.

Mystery Science Theater 3000

 * The character Flanksteak is a reference to Bold Flanksteak, one of the numerous names given by Mike and the bots to the beefy main protagonist in the Space Mutiny movie.

Oprah

 * While in combat, Axton can occasionally say "And YOU get a bullet, and YOU get a bullet! EVERYONE gets a bullet!" a reference to Oprah's energetic nature and giving audience members gifts.

Party Down

 * Some NPCs in Sanctuary ask the question "Are we having fun yet?", a line actor Adam Scott delivers with chagrin in the STARZ comedy series Party Down.

Pinky and the Brain

 * Zer0's skin "Pinky Has a Brain" is a reference to the animated television series Pinky and the Brain, featuring the 2 main colors (white and pink) of the protagonists and also referencing to the highly doubted fact in the series, that the character Pinky has a brain.

Predator

 * Salvador's skill "Sexual Tyrannosaurus" is a reference to the same phrase said by Blain Cooper in the early scenes of the movie.
 * Salavador's skill "Ain't Got Time to Bleed" was a line spoken by Blain Cooper.
 * The challenge "You're One Ugly Mother..." is a reference to what Major Alan "Dutch" Schaefer says when he sees the Predator unmasked.
 * The achievement, "Unseen Predator" could be a reference to the Predator's cloaking device since the icon shows Zero activating his invisibility.
 * In the loading screens, one of the tips refers to stalkers, saying "If it bleeds, you can kill it, etc.", alluding to one of Major Alan "Dutch" Schaefer's lines from the movie. It's also worth noting that stalkers can turn invisible so long as their shields aren't depleted.
 * The red text on the CHOPPER is a reference to the line "get to the chopper" in the movie.

The Princess Bride

 * Some higher level rat enemies are labeled as "R.O.U.S", a reference to the Rodents Of Unusual Size. Additionally, one of the assassins from the "Assassinate the Assassins" mission, Assassin Rouf, is a gigantic rat.
 * The Gunzerker's "Inconceivable" skill is a line frequently stated by Vizzini from The Princess Bride.
 * Psychos will also occasionally say "Inconceivable!"
 * One of the Gunzerker's skins, "Indigo Montoya", is a reference to Inigo Montoya from The Princess Bride.

The Professional

 * Jack yells out "Bring me everyone! EVERYONE!" The reference being what Norman Stansfield yelled, in the movie, wanting all of the police at the scene.

Pulp Fiction

 * The challenge "Say Watt Again!" is a reference to the crime film Pulp Fiction's character Jules Winnfield who uses this line during an interrogation.

Reservoir Dogs

 * Axton's skin, "Mister Blonde" is a reference to the 1992 Quentin Taratino movie where all the hitmen were named after colors, including a Mister Blonde, played by Michael Madsen.

Rocko's Modern Life

 * The mission "Rocko's Modern Strife" is a reference to the cartoon Rocko's Modern Life.
 * The NPC for the mission, Rocko, wears a helmet with a jagged edge protruding from the bottom. The edge looks similar to a pair of buck teeth, which the main character of the cartoon possessed.

Rocky

 * The title of Eat Cookies and Crap Thunder is in reference to a line in Rocky, said by Rocky's trainer "...you're gonna eat lightning and crap thunder!"

Spaceballs

 * A Badass Loader caravan can be in Wurmwater. Killing the group Badass will grant a Badass challenge titled "Comb The Desert". This is a reference to a popular joke in the movie Spaceballs, Dark Helmet orders his men to "comb the desert", they misinterpret his orders and use literal giant combs.

Saturday Night Live

 * One of Maya's skins, "Light Urple", is an answer given by one of the contestants in SNL Celebrity Jeopardy when asked to give the only color that ends in "Urple".
 * Scooter says "strategery" instead of "strategy" (shortly after installing the first power cell during the Plan B mision). The same mispronunciation was used by Will Ferrell during a parody of the 2000 Bush-Gore debates, in which Ferrell played then-governor George W. Bush.

Sealab 2021

 * Two of Gaige's skills under the "Little Big Trouble" tree are references from the show:
 * "Strength of Five Gorillas" refers to the hypothetical strength of robot bodies according to Sparks in the episode "I, Robot". Marco repeats it while lamenting the short height restrictions of the bodies.
 * "Wires Don't Talk" is a quote from Stormy in the episode "Lost in Time".

Serenity

 * One of Zero's available costume skins is "Leaf on the Wind", which is a reference to something Alan Tudyk's character Wash says during the final airborne battle. Similarly, there is a sniper rifle challenge called "Leaf on the Second Wind."
 * One of Salvador's available costume skins is "Let's Be Bad Guys", which is a quote from Adam Baldwin's character Jayne Cobb in the series.

Se7en

 * Gwens head.jpg opening a cardboard box in The Goose's Roost, Handsome Jack will yell: "What's in the booooooox?!" There is a female head in the box and a gun named Gwen's head, a reference to the movie Se7en.
 * The introduction text for Best Mother's Day Ever, in which players try to gain access to a locked chest, is "WHAT'S IN THE BOOOOOOOOOOOOOOX?!"

Shaun of the Dead

 * One of Maya's available costume skins is named "Slice of Fried Gold" which is a reference to zombie-action-comedy flick Shaun of the Dead.

Short Circuit

 * When Deathtrap gets a kill, sometimes Gaige will scream "Number 5 alive!"

Silent Night, Deadly Night 2

 * Sometimes after killing an enemy while Gunzerking, Salvador will shout out "Garbage day!", a reference to an infamous line from the movie and internet meme.

The Simpsons

 * In Sanctuary, an NPC can be heard saying "I must go, my people need me.", a line similar to one spoken by Poochie in the 8th season episode "The Itchy & Scratchy & Poochie Show".
 * The Gunzerker's skill "Bus that can't Slow Down", is a joke from the beginning of the 8th season episode "The Springfield Files".

Star Trek

 * The "Greenblood" Siren skin is a possible reference to the common insult to Vulcans in the Star Trek series.
 * Zer0 has a skin called "Red Shirt", a reference to the colloquial name given to Starfleet security officers and the color uniforms they wear.

Star Wars

 * When Claptrap is first encountered, he will introduce himself by saying "Allow me to introduce myself - I am CL4P-TP, steward bot..." This could be a reference to the introduction C-3PO often used in the Star Wars franchise. "Allow me to introduce myself - I am C-3PO, Human-Cyborg Relations."
 * The challenge "That's Impossible, Even for a Computer," in which a player must lob a grenade into an exhaust port, refers to Wedge Antilles's objection when the Rebel forces were planning the attack on the Death Star, also during Episode IV: A New Hope.
 * When trying to enter Hero's Pass, Claptrap is fiddling an access panel at the bottom right of the door. Accidentally he triggers a set of blast doors, replicating the Endor bunker scene in Episode VI: Return of the Jedi.
 * Upon gaining a stack of Anarchy, Gaige will sometimes shout "Unlimited power!", much like Senator Palpatine in Episode III: Revenge of the Sith.
 * The Sand Skiff vehicles included with the Captain Scarlett DLC are modeled after the skiffs used by Jabba's guards in Episode VI: Return of the Jedi.
 * The Assassin skill 'Death Mark' includes the text: "Plus, it's not an easy thing to live with." This is a reference to Episode V: The Empire Strikes Back when Han Solo tells General Rieekan that he has to leave to pay off Jabba. Rieekan responds with: "A death mark's not an easy thing to live with."

Super Troopers

 * Salvador will sometimes yell "I am all that is man!" while gunzerking, referencing the syrup chugging scene.

Take The Money And Run

 * The unique pistol Gub and it's flavor text is a reference to the bank robbery scene, where Virgil tries to hold up a bank with a note that says "Please abt naturally. I am pointing a gub at you."

Talladega Nights

 * The challenge "If You're Not First, You're Last" is the catchphrase of main character and NASCAR star Ricky Bobby.

Teenage Mutant Ninja Turtles

 * The side mission "Splinter Group" includes multiple references to TMNT. The mission involves delivering a pizza to a sewer system with four mutant inhabitants: Lee, Dan, Ralph, and Mick. Once the mutants realize the player isn't "June", they'll attack. At the end of the area there is a subway-style room with a couch and a TV (itself another reference to TMNT), a set of four switches, and five lights on the wall. If all of the lights go green, a boss rat called "Flinter" will appear.
 * Zero can use an unlockable skin called "Mutant" that places a blue stripe on the Assassin's head. The skin is a reference to Leonardo, who also uses a katana and wears a blue headband.
 * The QR Code on the pizza box in Moxxi's place scans as "Wise man say forgiveness is divine but never pay full price for late pizza. - Captain Picard". The misquote is from the first TMNT movie (Captain Picard never said this).

The Terminator

 * The Challenge "Hovernator" from the Captain Scarlett DLC is likely a nod to Arnold Schwarzenegger's role as the Terminator in the film The Terminator.
 * The same could be said about the E-Tech Pistol, the Dahlminator
 * When Gaige's Deathtrap kills an enemy, she sometimes says "Terminated".

The Scarlet Pimpernel

 * The Pimpernel sniper is given as a mission reward. Along with being named after the film, it has red text saying "Sink me!" a phrase used by several times by the film's protagonist Sir Percy Blakeney.

They Live

 * Salvador's skill "All Out of Bubblegum" is a reference the phrase "I've come here to chew bubblegum, and kick ass... and I'm all out of gum," a line from the 1988 film "They Live" and famously used in another Gearbox game by the main character, Duke Nukem. In all likeliness this was added because of Duke Nukem.

Titanic

 * The challenge "King of the Buzzard World" is a reference to the film Titanic in which Leonardo DiCaprio's character yells, "I'm king of the world!"

Tombstone

 * Salvador's skill "I'm Your Huckleberry" is a line often spoken by Doc Holliday in the film.

Top Gun

 * The mission Too Close For Missiles is a reference to the movie Top Gun, and how one of the prominent musicians in the film is Kenny Loggins. When it is turned in he will say, "You can be my wingman any time." Also during the climax of the mission players battle shirtless volleyball players.
 * The same character, Loggins, will say several quotes from the movie when spoken to.
 * On the Top Gun film soundtrack one of the main artists is Kenny Loggins. Within the dialogue of Loggins he quotes "Take My Breath Away" and "Danger Zone", both of which are tracks from the album (the latter having actually been performed by Kenny Loggins).

Tora! Tora! Tora!

 * Buzzards will occasionally shout "Tora! Tora! Tora!" (Japanese for "Tiger! Tiger! Tiger!"). Historically, "Tora" was a code phrase used by the Japanese during their attack on Pearl Harbor in 1941. The phrase was later used as the title of a movie about the attack. It was also used in Worms Armageddon for that matter, as one of the sounds of the Kamikaze attack, given the way it is said in the game it may very well have been inspired from there.

Towering Inferno

 * A challenge is named "Cowering Inferno", which is a reference to the 1974 film, Towering Inferno.

Transformers

 * Claptrap will sometimes say, "Minion, roll out!", which paraphrases the transformation command given by Optimus Prime in the original "Transformers" series.
 * The JET variant of Loaders are also a reference to Transformers, as they share the same color scheme and capabilities as one of the main Decepticons, Starscream.
 * The legendary shield Transformer bears the flavor text "There's more than your eye can see." which is a reference to the series' motto, "More than meets the eye."
 * The skill Made of Sterner Stuff refers to a line spoken by Optimus Prime in the 1986 animated movie.

Yellow Submarine

 * The challenge "Green Meanie" is a reference to either the Blue Meanies from The Beatle's film "Yellow Submarine" or the professional wrestler "The Blue Meanie".

The Young Ones

 * Zer0's "Bored" haiku is a reference to The Young Ones, a 1980's British sitcom. In one of the episodes, the character Vyvyan goes around swinging a cricket bat while shouting "BORED!" and smacking another character over the head with said bat.

Yu-Gi-Oh

 * When using Zer0's Decepti0n, he sometimes says, "How hilarious. / You just set off my trap card -- / Your death approaches." in reference to Yu-Gi-Oh, and the phrase was often used on the Internet.

Wall-E

 * There is a massive Loader named H3RL-E in the mission "Whoops".

What Ever Happened to Baby Jane?

 * The side mission "Handsome Jack Here!" begins with the message found on the first ECHO recorder's description that reads "What ever happened to Elena Pierce?".

Willy Wonka

 * The gun Veruc is a refernce to the golden ticket girl Veruca Salt. With the text "I want this rifle daddy" are reference to the golden egg (or squirrel according to the book) she demands for her father to acquire.

Zardoz

 * There is graffiti in the Bloodshot Stronghold that depicts Marcus vomiting up guns that reads "Marcus Gunbringer". This is a reference to the 1974 film "Zardoz".

Zoolander

 * There is a Runner skin called Blue Steel, named after Derek Zoolander's iconic look in Zoolander.

Red Harvest / Last Man Standing / Fistful of Dollars

 * At the end of the mission Clan War: First Place Ellie says, "After this red harvest, you'll be the last one standing with a fistful of dollars. Yo jimbo." Fistful of Dollars is a Clint Eastwood western that is based on a samurai film called Yojimbo (both of which are based on the Dashiell Hammet novel Red Harvest) and Last Man Standing is a similar movie starring Bruce Willis.

Acclaim logo

 * The description of the challenge Critical Acclaim, "Kill enemies with critical hits. And rainbows" is a play on the game publisher Acclaim's logo bearing a rainbow on the bottom of it.

Altered Beast

 * When the player is respawned, one of the phrases spoken by the New-U station's AI is "Rise from your grave." This is a direct reference to the same phrase spoken during the intro of Altered Beast.
 * There is a Gunzerker class mod called "Altered Beast".
 * One of Maya's skills in the Harmony tree has the description, "Rise from your grave."

Amnesia: The Dark Descent

 * Captain Flynt will drop "Flynt's Tinderbox", a Bandit pistol with flavor text that reads: "Good for starting fires." This is a reference to the popular psychological horror game, Amnesia: The Dark Descent, which has items called Tinderboxes with the same description.

BattleToads

 * The "Toad of Battle" skin for Zer0 is a reference to the extremely challenging NES game BattleToads, not only with the name, but also with the Green, Black, and Yellow colors.

BioShock

 * In the Captain Scarlett DLC, there are two uniquely named enemies: Mr. Bubbles, is named after the title Little sister give Big Daddies, and Lil Sis, who appears as a pirate midget.

Borderlands

 * The sniper rifle, Trespasser is named after Mordecai's skill Trespass and shares the same ability for shots to bypass an enemies shields. The red text that reads: "I infrequently perish" is a reference to the line Mordecai says when he gets downed in the first game, "I never die."
 * When meeting Mordecai for the first time in Sanctuary after Bloodwing's death, Lillith and Roland can be heard talking about an instance when Mordecai got shot in the shoulders and sent bloodwing to fight some bandits, but bloodwing fails to do so until Mordecai faces the bandit. A possible reference to the original Borderlands in the instance that bloodwing cannot attack enemies that Mordecai cannot see.
 * There is a weapon, "Sledge's Shotgun", with the red text that reads: "The legend lives!" This is a reference to the Sledge's Shotgun in the first Borderlands. Several other Legendary weapons return, such as the Hellfire, usually bearing red text that references the original weapon's red text.
 * Any 'Legendary' Class mod gives a quote from the corresponding character from the previous game, for example, Zer0's Legendary Hunter class mod uses Mordecai's 'I NEVER DIE' quote as the red text.

Call of Duty series

 * The challenge "Call of Booty" and Axton's skill "Duty Calls" are references to the Call of Duty series of games.
 * Zer0's head "Gh0st" is similar to that of the character Ghost from Modern Warfare 2.

Crackdown

 * Zer0's skin "Blue Light Special" is possibly a nod to the Crackdown series of games.

Dark Souls

 * In the Caustic Caverns, there is a small island with an NPC named Solitaire sitting on a ledge in front of a bonfire. White phantoms can also be seen sitting in front of the bonfire. This is a reference to the video game Dark Souls, with Solitaire being a reference to the knight Solaire of Astora.
 * Axton can get the helmet that Solitaire is wearing, it is called Space Knight.
 * The New-U Stations in Tiny Tina's Assault on Dragon Keep sometimes say the phrase "Hollow Reversed."
 * The optional mission Lost Souls is full of references to the gameplay of Dark Souls:
 * The mission is given by the Crestfallen Player, who is a reference to the Dark Souls NPC the Crestfallen Knight.
 * When accepting the mission the desciption reads: "Amazing loot ahead" as well as advising players to bring a fire weapon. In Dark Souls, players can leave various hints and warnings for each other such as "Amazing treasure ahead" this can also be true when he warns them to "Be wary of traps"
 * The mission objective is to collect souls from slain enemies for the undead knight so he can use them to regain his humanity, which is one of the core mechanics in Dark Souls.
 * Bonfires feature prominantly in Dark Souls, but serve as checkpoints instead of spawning enemies.
 * After the Crestfallen Player uses the souls to regain his humanity he will then be "invaded" by -=n00bkiller=- who, similar to invading players in Dark Souls, glows red.
 * Upon killing -=n00bkiller=- the Crestfallen Player remarks "Try stabbing me in the back while I drink from my flask now jerkwad!"  In Dark Souls the main healing item is known as an "Estus Flask" and players in PvP will often take advantage of the lengthy animation to use one to stab their oppenent in the back for bonus damage. A tactic that is frowned upon by most of the player community.

Demon's Souls

 * Marcus Kincaid's gun vending machines will sometimes sign off with "Don't die, I need your business!", an echo of what Blacksmith Boldwin says to you in the Nexus.

Dead Space

 * One of Zer0's unlockable heads, 3ng13 ("Engie"), is of a similar design to the helmet of Isaac Clarke, the main protagonist of Dead Space, and is named after his in-game profession, that of a systems engineer.

Donkey Kong

 * There is an enemy named "Donkey Mong" who throws barrels and wears a tie. He is a reference to the game and the character of the same name.
 * The achievement called "Definitely an Italian Plumber" whose icon is a barrel makes a reference to Donkey Kong as well.

DOOM

 * The title PBFG for E-tech Rocket Launchers is a reference to the BFG ("Big Fucking Gun") from The DOOM series, meaning "Pretty Big Fucking Gun".
 * The Topneaa series of E-Tech rocket launchers cause damage in the similar manner as the BFG. The launcher will fire a single projectile, that when it detonates will inflict splash damage over a large distance. This is similar to the BFG's area of effect animation.
 * Here is a video showing the Topneaa in action.

Driver: San Francisco

 * An NPC in Sanctuary can occasionally say "I was playing this Echo Sim where you could jump into trucks with your mind. It's pretty much the best thing ever." This is a reference to Gearbox writer Anthony Burch's love for Driver: San Francisco.

Dwarf Fortress

 * Salvador's "Boatmurderer" head, a dwarvern-style beard and spiked mohawk, is a reference to Boatmurdered, an infamous Dwarf Fortress succession game from Something Awful.

Fallout series

 * There is a Bandit Shotgun called Thre Dog. The red text says "Because one barrel ain't enough, and two is too few." This is referencing the character Three Dog the radio broadcaster from the Bethesda game Fallout 3. Both of these reference the song "One" by the band Three Dog Night.
 * The skin "Vault Dweller" for the Siren is a reference to the outfits worn by the members of the vaults from the Fallout series. It follows its color pattern with blue body and yellow highlights.

Final Fantasy series

 * In the Challenges, there is a challenge in the melee section called, "A Squall of Violence". This is a reference to Squall Leonhart from Final Fantasy VIII, who used a gunblade, which was a gun that had a sword on the end. The challenge is for killing enemies with melee attacks using a bladed gun.

Frogger

 * One of the unlockable heads for Gaige is named Fragger, which is a reference the the old arcade game Frogger.

Gears of War

 * One of the heads for Zer0, "C0al Train" which is a football helmet, is a reference to Cole from the Gears of War series, who is a football player, and goes by the nickname "Cole Train".

Half-Life

 * In the mission No Vacancy, the objectives include "Find Steam Valve", and "Find Gearbox". These are references to Valve, and its platform Steam, and Gearbox, the developer of the game. A similar set of objectives appeared in a stage of one of the first Gearbox games, Half Life: Opposing Force.
 * Zer0's skin "This is HEV-y" which is a rare drop from King Mong in the Eridium Blight is a reference to the HEV suit used by Gordon Freeman.

Halo

 * Given their properties of shots slightly homing in on enemies and of shots exploding after a delay, in addition to the similar name, the "Needler" type E-tech pistols may be an homage to the Needler weapon present in the Halo series.

Mario Kart

 * The "Blue Sparks" vehicle challenge is a reference to the Mario Kart series.

L.A. Noire

 * Marshall Friedman can sometimes be heard saying "I say we bust in there and find the goddamn evidence!", a line usually uttered by random NPCs in L.A. Noire.

League of Legends

 * Midge-mong may be a reference to the Champion, Nunu, who is a young boy riding on a yeti named Willump.
 * Master Gee the Invincible may be a reference to the Champion, Master Yi.

Legend of Zelda

 * In Sanctuary, Crazy Earl will say "It's dangerous to go alone, jerkwad!" This is a reference to the famous Legend of Zelda quote.

Metal Gear

 * Geary, a midget in the Eridian Blight sometimes drops a face customization. The item is called Metal Fear which is a reference to the Metal Gear series.
 * When he has been seen, Zer0's display will sometimes show an exclamation point—a reference to the Metal Gear series of games.
 * Axton's head skin "Medic Mantis" is a reference to Psycho Mantis from the Metal Gear series.
 * The Thief Rats, on occasion, call out "The fear!" when attacked. This is a reference to the same named boss from Metal Gear Solid 3.
 * Some of the Crimson Raiders will describe Sanctuary as being "just outside heaven for soldiers like us. Always something to fight." References the ideals behind the founding of Outer Heaven.
 * The citizen inside Dr. Zed's clinic in Sanctuary occasionally says, "I feel asleep..." This is a line from the original Metal Gear on the NES.

Minecraft

 * There are several references to Minecraft in the Caustic Caverns. Some references include destructible blocks from the game, Creepers, and Minecraft-themed customization items. There is also a mission called "Minecart Mischief" where an objective is to push a minecart full of Eridium along rails.
 * There is a shotgun titled "Blockhead" with red text that reads: "Also try Minecraft!" Minecraft is known to promote other games in a similar manner using "splashes" when the game launches. The gun shoots projectiles in a 3x3 square formation.
 * There is another gun with the title "Longbow", which is a scopeless sniper rifle that shoots bullets which leave a pixelated trail, just like the arrows in Minecraft. The read text reads "Ceci n'est pas une sniper rifle!" Which then translates to "This is not a sniper rifle!" pointing out the fact that it has no scope.

NBA Jam

 * Axton, after a kill, will sometimes exclaim, "Boom-shaka-laka!", a phrase frequently uttered by the announcer in NBA Jam.

Orcs Must Die

 * In Tiny Tina's Assault on Dragon Keep, there is a challenge for killing orcs titled, "Orcs should perish."

Pokémon

 * In Mr. Torgue's Campaign of Carnage, Flyboy will say "I'm gonna be the very best, like nobody ever goddamn was!" in one of his pre-recorded messages in The Forge, a reference to the Pokémon anime series' first season theme song.

Resident Evil

 * One of the challenges is called "Waddaya Buyin'?", this is most likely a reference to Resident Evil 4's merchant trader whose dialogue consists of: "Waddaya Buyin'?" and "Waddaya Sellin'?"
 * Crazy Earl will sometimes ask "Waddaya buyin'?" as well.
 * The Infection pistol's flavor text "Itchy. Tasty." is a reference to the original Resident Evil, in which an animal caretaker who goes insane due to t-Virus infection chronicles its destruction of his sanity in his diary. More specifically, this refers to the final entry in the diary, where the keeper's flesh begins to rot, and the next day kills and devours a coworker.

Saints Row

 * Some Sanctuary NPCs will mention an ECHO sim about "The Gang That Wore Purple," a pretty obvious nod to the 3rd Street Saints of the Saints Row games.

SoulCalibur

 * One of Zer0's skins, 'Azure Knight', is a possible nod to the primary antagonist of the SoulCalibur series, Nightmare's ephitet.

Skyrim

 * In Sanctuary, NPCs can occasionally say "I used to be a Vault Hunter like you, until I took a bullet to the knee." This is a reference to the Bethesda game Skyrim, where guards often say "I used to be an adventurer like you, then I took an arrow in the knee.”
 * The NPC Face McShooty also makes a reference to the "Arrow in the Knee" meme, when listing the places he doesn't want to be shot; "Not the KNEE, not the ARM, not the SPINE - FACE!"
 * Roland also references the line when he first meets the Vault Hunters, saying "I used to be a Vault Hunter like you, until I founded the Crimson Raiders."
 * During combat, bandits will occasionally shout "Never should have come here!" in reference to a line a lot of Skyrim NPCs commonly say during battle.
 * In Tiny Tina's Assault on Dragon Keep there is a challenge for killing dragons called "Fus Roh Die".

Street Fighter

 * Axton's Shadaloo Styish head is a reference to Shadaloo, a criminal organization that appears in the Street Fighter series. The head itself is based on the hat worn by M. Bison, who leads the organization.

Team Fortress 2

 * The achievement "So Much Blood!" is a reference to the quote the Heavy will say when continuously firing his minigun. This is further reinforced by the fact the achievement is earned by gunzerking continuously for 90 seconds.

Unreal Tournament

 * The effect of one of Gaige's skills, One Two Boom, is a reference to the Shock Combo in the Unreal Tournament series, where shooting the electric ball from the Shock Rifle's alternate fire with its primary fire causes the ball to explode and deal damage to enemies around it.
 * Additionally, the tooltip flavor text for One Two Boom, "100% more Multi-Kill", is a reference to one of the series' killstreak awards.
 * If you kill multiple enemies in rapid succession as Gaige, she will say "M-m-m-monster kill!", which is another one of the series’ killstreak awards.

Warhammer 40,000

 * There is an assassin skin mod called "Ultramarine", referencing the Ultramarines, a Space Marine chapter with the same colors as the skin: blue, white, and gold, although the skin has a dirtier look.
 * It is possible that the Bandit weapons names are a reference to the Orc weapon's names in Warhammer 40K.
 * The Emperor SMG's red text, "you know... for him" is a reference to the Warhammer 40,000 universe, where the Imperium of Man uses "For the Emperor!" as a battle cry.

Warcraft

 * The challenge "For the Hoard" is a reference to the battlecry "For the Horde!" used by members of the Horde.
 * The Slag Scar located within the Eridium-Blight is a possible imitation of The Dead Scar from Warcraft. That both Scars are made of "blight" is further evidence for this association.

X-COM

 * The mission "Medical Mystery: XCOM-Municate" is a reference to the X-COM series of strategy games.

X-Men

 * Sometimes, Goliaths will say, "Welcome to die!", a reference to the infamous line spoken by Magneto in the 1992 X-Men arcade game.

You Don't Know Jack

 * The title of the mission "Get To Know Jack" is a reference to the You Don't Know Jack video game series.

AC/DC

 * The Campaign of Carnage mission Highway To Hell is a reference to the AC/DC song of the same name.
 * There is also the Campaign of Carnage mission Long Way To The Top, which is a reference to the AC/DC song "It's a Long Way to the Top (If You Wanna Rock 'n' Roll)".

Ain't No Rest For The Wicked

 * After killing the Warrior, Lilith will say "No rest for the wicked", a reference to the Cage the Elephant song "Ain't No Rest for the Wicked" which was used as the song in the beginning of the first Borderlands.
 * Rarely, NPCs will hum the song saying something in for most of the words

Afternoon Delight

 * "Afternoon Delight" is a challenge that references the song of the same name by Starland Vocal Band.
 * "Sky Rockets in Flight..." refers to a line used in the chorus of the song.

Best I Ever Had

 * At one point, Tiny Tina says "Shorty, you da best. You da you da best." This references the song "Best I Ever Had" by rapper Drake.

Bad Religion

 * Gaige has an unlockable skin called "Horrible Religion" which is a reference to the punk rock band Bad Religion.

Black Betty

 * The challenge "Woah, Black Betty" is a reference to the song Black Betty by blues singer Huddie "Lead Belly" Ledbetter. Lead Belly first recorded the song commercially in New York with the famous "Woah, Black Betty" lyrics in 1939. It became more popular after Ram Jam covered the song in 1977.

Bob Dylan

 * The mission Knockin' on Heaven's Door is a reference to his song "Knockin' on on Heaven's Door".

The Clash

 * Gaige has a skin called "Clashing Colors", which could be a nod to the extremely popular punk band, The Clash, presumed by Gaige's general punk rock theme.

Cool Guys Don't Look At Explosions

 * In the mission Toil and Trouble there is an optional objective to look away from the explosion in order to look more badass when the Boombringer is destroyed.

C.R.E.A.M

 * The "Dolla Dolla Bills, Y'all" challenge is a reference to a line used throughout the Wu-Tang Clan song "C.R.E.A.M."

Daft Punk

 * Zer0's Punk helmet is dropped by Boll during the mission In Memoriam. It resembles the helmet worn by band member Guy-Manuel de Homem-Christo.

Dazed and Confused

 * The achievement, "Phased and Confused" is a reference to a signature song "Dazed and Confused" by Led Zeppelin.

Dead Kennedys

 * Gaige has an unlockable skin called "Dead Lincolns" which is a reference to the punk rock band Dead Kennedys.

Diamonds Are a Girl's Best Friend

 * The challenge "Crystals Are a Girl's Best Friend" is a reference to the song "Diamonds Are a Girl's Best Friend" used in the musical Gentlemen Prefer Blondes.

Earth, Wind & Fire

 * "Death, Wind, and Fire" references the disco band Earth, Wind & Fire.

Foreigner

 * The achievement, "Feels Like The First Time" is a reference to Foreigner's hit song by the same name.

Foux du Fafa

 * After completing the fifth circle of death for Innuendo-bot 5000 in Ore Chasm, the final reward is a sniper rifle called Monstrous Chere-amie with the caption "Je suis enchante, Ou est la biblioteque?" referencing the song Foux du Fafa a song by Flight of The Conchords.

Frank Turner

 * Gaige's ability "The Better Half" could possibly be a reference to the Frank Turner song "Better Half", assumed so due to her overall punk rocker design.

Genesis

 * Sometimes a Psycho will yell, "A flower!", when running at the player. This is a reference to a line in the Genesis song "Supper's Ready".

Green Day

 * The Gunzerker skin "A Green Day" is a reference to the band Green Day.

Guns N' Roses

 * The Campaign of Carange mission Battle: Appetite for Destruction is a reference to the Guns N' Roses salbum "Appetite for Destruction"
 * Another Campaign of Carnage mission Welcome to The Jungle shares its name with a song from Appetite for Destruction

Hungry Like The Wolf

 * The side mission "Hungry Like the Skag" is a reference to Duran Duran's song "Hungry Like the Wolf".

I Believe I Can Fly

 * Sometimes when phaselocked, a bandit will say, "I believe I can fly.", a reference to a song of the same name by R. Kelly.

I Don't Want To Set The World On Fire

 * Miss Moxxi's Heart Breaker has red text that reads "I don't want to set the world on fire..." A reference to the song of the same name by The Ink Spots.
 * There is also a challenge "I Just Want to Set the World on Fire".

I Love the Nightlife

 * The challenge "...I Got to Boogie" for killing enemies at night is a reference to a line in Alicia Bridge's song "I Love the Nightlife".

I Shot the Sheriff

 * In the mission Showdown there is an optional objective for killing the sheriff that reads, "But do not shoot the Deputy". This is a reference to the song "I Shot the Sheriff" originally by Bob Marley and The Wailers (but made popular by Eric Clapton). The chorus of the song is, "I shot the sheriff, but I did not shoot the deputy."

(If Loving You Is Wrong) I Don't Want To Be Right

 * The flavor text on the Love Thumper shield is a reference to the song by Luther Ingram.

In the Hall of the Mountain King

 * Sometimes while Gunzerking, Salvador will hum Edvard Grieg's famous "In the Hall of the Mountain King".

Joy Division

 * Gaige has an unlockable skin called "Joy Divide", a nod to Joy Division.

Mötley Crüe

 * The mission Kickstart My Heart is a reference to their song "Kickstart My Heart".

Never Gonna Give You Up

 * When killing a Psycho, they may say "Never gonna give you up..." This is an allusion to the popular Rick Astley song of the same name.

No. 5

 * A Sanctuary citizen in Moxxi's will sometimes say "Can't stop! Won't stop!", a line from Hollywood Undead's song No. 5.

NOFX

 * Gaige has an unlockable skin called "YesFX".
 * Gaige has an unlockable skin called "Don't Call Her Green" a possible to reference to NoFX song "Don't Call Me White".

Purple Haze

 * The Axton skin "Purple Haze" is a reference to a Jimi Hendrix song of the same name.

Purple Rain

 * The challenge "Purple Reign" is a reference to Prince's song, album, and film, "Purple Rain".

The Ramones

 * Gaige has an unlockable skin called "Miss RAMONE". This can be assumed to be a reference to american Punk Rock band The Ramones.

Rancid

 * Gaige has an unlockable skin called "Citrus Salvation", which could possibly be a reference to the Rancid song, 'Salvation'.

Junior Senior

 * A Sanctuary Citizen residing in Moxxi's may sometimes say "Can't Stop Won't Stop!", this may be a reference to Junior Senior's song 'Move your Body', where the lyric goes "Cant Stop Won't Stop can't stop the beat!".

Sex Pistols

 * Gaige sometimes says "Anarchy On Pandora!" when gaining a stack of anarchy, a reference to the Sex Pistols song "Anarchy In The UK".

Skills To Pay The Bills

 * Challenge "...To Pay the Bills" is a reference to the Beastie Boy's song "Skills To Pay the Bills".

Social Distortion

 * Gaige has an unlockable skin called "Distorted Socially", a reference to the punk band Social Distortion.
 * Gaige also has another skin called "Bye Bye Baby", which could either be a reference to the Social Distortion song, or the song written by Joey Ramone.

Under Pressure

 * "Under Pressure" challenge is a reference to the Queen (featuring David Bowie) song "Under Pressure".

Wilhelm Scream

 * The achievement "Wilhelm Screamed" is a reference to the Wilhelm Scream.

Alexander Pope

 * The missions "Where Angels Fear to Tread" and "Where Angels Fear to Tread (Part 2)" are taken from the line "Fools rush in where angels fear to tread." by Alexander Pope.

The Blue Meanie

 * The challenge "Green Meanie" is a reference to either the Blue Meanies from The Beatle's film "Yellow Submarine" or the professional wrestler "The Blue Meanie".

Bruce Lee

 * Zer0's skill "Be Like Water" is a reference to Bruce Lee famous "be like water" quote.

H.M. Stanley

 * In the DLC Sir Hammerlock's Big Game Hunt, the mission entitled "Professor Nakayama, I Presume?" is a reference to H.M. Stanley's famous greeting, "Dr. Livingstone, I presume?"

Isaac Asimov

 * The PA system in Hyperion areas tell the loaders to "Remember your three laws..." referencing the three governing laws of the robots created by Asimov.
 * Loaders, upon entering combat, will sometimes say "First Law disabled.", a reference to the first law of robotics; "A robot may not injure a human being or, through inaction, allow a human being to come to harm.

James Watt

 * Assassin Wot is a play on the name of Ronald Reagan's Secretary of the Interior. Wot drops an SMG with the red text "I have a soldier, a siren, two Scooters and a claptrap", a mimicking of Watt's quote, when challenged about diversity in his department that, "I have a black, a woman, two Jews and a cripple."

Jasper Foreman

 * The enemy Foreman Jasper is a play on the name of Jasper Foreman, head of AI design for Gearbox.

Jean-Claude Van Damme

 * The challenge "The Van Is Damned" is a play on his name.

Jameson Whiskey

 * In Southern Shelf, north of the exit to Three Horns - Divide right across the gap in the ice is a floating barrel that reads 'Gamerson Whiskey' which is a reference to Jameson Irish Whiskey.

Lucky Charms

 * The mission "Clan War: Follow the Rainbow". When first gotten its description says nothing but, "Hearts, Stars, and Horseshoes...". This is the beginning of the lucky charms Jingle.

Mobil

 * The Catch-a-Ride logo is a play on the gas company Mobil's logo.

National Rifle Association

 * The challenge for assault rifles "From My Cold Dead Hands" is taken from the Nation Rifle Association's slogan "I'll give you my gun when you pry it from my cold, dead hands."

Samuel Butler

 * A grenade called the Leech has red text that reads: "A skillful leech is better far, than half a hundred men of war." This is a quote made by Samuel Butler.

Sarah Palin

 * There is a gun with red text that reads: "Don't retreat, instead reload!" This is a reference to Sarah Palin's similar phrase.

United States Postal Service

 * The mission Neither Rain Nor Sleet Nor Skags is a reference to the unofficial motto of the USPS.

Theodore Roosevelt

 * In the Sir Hammerlock DLC, a unique shield called "The Rough Rider" can be found, bearing the red text "it takes more than that to kill a Bull Moose".

Verizon Wireless

 * The challenge "Can You Hear Me Now" is a reference to the popular Verizon Wireless ads.

Wasteland Panda

 * There is an abandoned gas station in The Dust with a slot machine inside; on the wall to the left of it is a stencil of the panda from "Wastelander Panda."

Swag

 * Dr. Zed's vendors will randomly say "Who needs a medical license when you've got style?" A reference to the "Who needs 'X' When you've got swag?" Pictures

Cool story, bro

 * After getting a kill, Axton will occasionally say "Cool story, bro." This is a reference to the phrase used in response to a lengthy, off-track, or obviously fake story.
 * Similarly, the woman being talked at by a drunk outside Moxxi's will sometimes respond with "Super cool story, bro."
 * Killing Handsome Jack at the end of the game gives the "Cool Story, Bro" achievement.

Come At Me, Bro

 * When recharged the 1340 Shield will sometimes say " Come At Me." This is likely a reference to the meme Come At Me, Bro.

Don't Copy That Floppy

 * The second mission that C3n50r807 gives is titled "Don't Copy That Floppy", a reference to a viral video campaigning against software piracy.

Double Rainbow

 * The achievement "What does it mean?" is unlocked when seeing a double rainbow in the skies of The Highlands. This is a reference to a viral video of someone overly excited about a double rainbow.


 * Psychos will also occasionally shout "What could it all mean?" which is likely a reference to the "Double Rainbow" video.

Dragon Ball Z

 * The dials on each radio on Pandora show each hundred from 100 to 800. What should be "900" is actually "9001" in reference to the "It's over 9000" meme. Borderlands 2 Dragon Ball Z Easter Egg

Haters Gonna Hate

 * The challenge "Haters Gonna Hate" is a reference to the meme of the same name.

Leeroy Jenkins

 * The challenge "JEEEEENKINSSSSSS!!!" is part of the famous phrase where he shouts his name and runs blindly into a dungeon in World of Warcraft.

Neil DeGrasse Tyson Reaction

 * While fighting a badass enemy after finding Lilith, she will sometimes say "Watch out, we've got a badass over here." This is a reference to the Neil DeGrasse Tyson meme of a similar title.

Pirates vs. Ninjas

 * In True Vault Hunter Mode, Corsairs in Captain Scarlett and Her Pirate's Booty are renamed Pirate Ninjas, a reference to the theoretical conflict between pirates and ninjas.

Shoop da Whoop

 * Constructors, before using their laser attack, will occasionally say "I'm charging mah lazer." a phrase associated with the "Shoop da Whoop" meme.

Super Cool Ski Instructor

 * One of the loading screen tips will say "if you fight a fire skag with a fire gun, you're gonna have a bad time." This is a reference to the South Park ski instructor meme.

U Mad?

 * The challenge 'U (No)Mad Bro?' is a reference to the "U MAD?" internet meme.

Xzibit Yo Dawg

 * One of the challenges is called "Yo Dawg, I heard you like challenges." in reference to the Xzibit meme.

Fuck Yeah

 * Some badass nomads have a piece of metal with the Fuck Yeah meme on it attached to their shield.

#YOLO

 * Suicide Psychos sometimes scream "YOLO!" prior to detonation. This is a reference to the often hated #YOLO trend, spawned on the social network Twitter.