Axton/Skins

Skins available and unlockable for Axton. There are 20 heads and 89 skins to collect in total for Axton.

Heads
 Default 
 * Axton
 * Radar Ranger
 * Wetworker

 Unlockable 
 * Dapper Gent - Rare drop from Henry the Stalker
 * Gallant Grunt - Complete To Pay The Bills
 * Grizzled Veteran - Mission reward for completing Symbiosis as Axton
 * Handsome Jack's Mask - dropped by Handsome Jack
 *  - Dropped by killing Geary; rare drop from The Warrior
 *  - Dropped by Creepers
 * Bone Blinder - Rare drop from Vermivorous the Invincible
 * Roguish Renegade - Mission reward for completing In Memoriam as Axton
 *  - Random Drop
 * Shadaloo Stylish - Rare drop from Terramorphous the Invincible
 * Space Knight - Rare drop from BNK3R
 * Special Edition - Snowblind - Special Edition DLC Skin; can be obtained via trading
 * The Hawk - Mission reward for completing Statuesque as Axton
 * Vault Veteran: Lancer - Have game save from Borderlands
 *  - Mission reward for X Marks The Spot in Captain Scarlett and Her Pirate's Booty
 *  - Acquired in Mr. Torgue's Campaign of Carnage DLC
 * Clever Boy - Acquired in Sir Hammerlock's Big Game Hunt

 Downloadable 

Note: It is not known, at the time of this edit, if Downloadable skins and heads are placed into one's ingame inventory or unlocked in the customization menu directly.
 * Headbanger - Commando Domination Pack
 * Covert Op - Commando Supremacy Pack
 * Ex-Axton - Commando Madness Pack

Skins
 Default 
 * Axton's Regulations Attire
 * Axton's Blue Period
 * Bluegrass
 * Blue Serenity
 * Bright Boy
 * Bright Idea
 * Burning Love
 * Double Down Browntown
 * Do or Die
 * Fade to Blue
 * Greenback
 * Gruff Around the Edges
 * Marooned
 * Red Fraction
 * Red Right Hand
 * Rough and Tumble
 * Scurvy Prevention
 * Snake in the Grass
 * Undah Da Sea

 Unlockable 
 * At Arms - Mission reward from Shielded Favors
 *  - Rank 3 "EXPLOOOOOSIONS!" challenge
 *  - Item of the Day
 * Bandit Incineration - Rank 5 "Knee Deep in Brass" challenge
 * Bandit War Paint - Rank 3 "Marauder? I Hardly Know 'Er" challenge
 * Black Ops - Rare drop from any of the four Hyperion Assassins
 * Blue Bomber - Rare drop from Son of Mothrakk
 * Dahl Efficiency -
 * Dahl Elite - Item of the Day
 * Dahl Predator - Rank 5 "Crouching Tiger, Hidden Assault Rifle" challenge
 * Dark and Light - Rare drop from Dukino's Mom
 * Denim Dynamo - Rank 3 "Aggravated Assault" challenge
 * Double Down Browntown -
 * Fierce and Flowery - Rare drop Vermivorous the Invincible
 * Fire and Forget - Rank 3 "The Killer" challenge
 * Gearbox - Only available to Gearbox Software employees
 * Golden Boy - Rank 3 "Blue Sparks" challenge
 * Greener Pastures - Rank 3 "It Ain't Easy Looting Green" challenge
 * Green Beret - Mission reward from The Cold Shoulder
 * Greenhorn - Rank 3 "Super Novas" challenge
 * Grey Matter - Rank 3 "Not Full of Monkeys" challenge
 * He's On Fire - Rare drop from Captain Flynt
 * Heating Up - Rank 3 "Pull the Pin!" challenge
 * Hyperion Heroism - Rank 3 "Load and Lock" challenge
 * Hyperion Honor - Item of the Day
 *  - Rank 5 "Eviscerated" challenge
 *  - Rank 3 "For the Hoard!" challenge
 * It's Kinda Easy being Green -
 * Jakobs Family - Mission reward from Capture the Flags
 *  - Rank 5 "Quick Draw" challenge
 *  - Item of the Day
 * Last Boy Scout - Rank 5 "This Is No Time for Lazy!" challenge
 *  - Rare drop from King Mong
 * Maliwan Elegance - Rank 5 "Slag-licked" challenge
 * Maliwan Grace - Rank 5 "I Just Want to Set the World on Fire" challenge
 * Maliwan Style - Item of the Day
 * Midnight Sky - Rank 3 "Longshot" challenge
 *  - Random drop from Creepers
 * Miss O'Hara - Rank 3 "Rocket and Roll" challenge
 * Mister Blonde - Rare drop from Saturn
 * Pandoran Legend - Have game save from Borderlands
 *  - Rank 5 "Nothing Rhymes with Orange" challenge
 * Patient - Acquired in Sir Hammerlock's Big Game Hunt
 * Purple Haze -
 *  - Mission reward from To Grandmother's House We Go
 * Purple Prose - Rank 5 "Badass Bingo" challenge
 * Purple Sun - Mission reward from No Vacancy
 * Radioactive - Rank 3 "Super Novas" challengehttp://www.lcplin.org/
 * Real Men Wear Pink -
 * Red Letter Day - Random drop from "Chubby" mobs
 *  - Rank 3 "Hail of Bullets" challenge
 * Self Azured - Rank 3 "Open Pandora's Boxes" challenge
 * Shadowy Warrior -
 *  - Rank 3 "Fisticuffs" challenge
 * Special Edition: Fired Up - Special Edition DLC Skin; Can be obtained via trading
 * Special Forces - Mission reward from The Overlooked: Medicine Man
 * Tediore Customer Service - 777 on slot machines
 * Tediore Low Price - Item of the Day
 * Tediore Value - Rank 5 "Boomerbang" challenge
 * The Grass is Greener - Rank 4 in "Whaddya Buyin'" challenge
 * The Half-Shell -
 * The Man With the Golden Pun - Rank 3 "Shotgun!" challenge
 * The Pink Panzer - Rare drop from Terramorphous the Invincible
 * Torgue Explosiveness - Rank 3 "BOOM" challenge
 *  - Item of the Day
 * Torgue Speed Demon - Rank 5 "Catch-A-Rocket!" challenge
 *  - Rare drop from threshers
 * Urban Jungle -
 * Vladof Freedom - Rank 5 "Ammo Eater" challenge
 *  - Item of the Day
 * Vladof Sickle - 777 on slot machines
 * Volcanic - Rare drop from spiderants
 * White Knight - Rare drop from threshers
 *  - 2012 SHiFT promotional skin

 Downloadable 

Note: It is not known, at the time of this edit, if Downloadable skins and heads are placed into one's ingame inventory or unlocked in the customization menu directly.
 * Crash Test Soldier - Commando Domination Pack
 * Advanced Warfare - Commando Supremacy Pack
 * Delicious Flesh - Commando Madness Pack

Trivia

 * The Shadaloo Stylish head is a reference to Street Fighter antagonist M. Bison and his criminal organization, Shadaloo.
 * The Medic Mantis head is a reference to a Metal Gear Solid Boss : Psycho Mantis.
 * The Clever Boy head is a reference to the character Robert Muldoon from Jurassic Park.
 * The Half-Shell skin is a reference to Teenage Mutant Ninja Turtles' Tag-Line: Heroes in a Half-Shell!
 * The Blue Bomber Skin is a reference to Capcom's Megaman whose nickname is "Blue Bomber".
 * The Black-Ops Skin is a reference to the Black Ops Division from the U.S. Military.