Enemies

The are three general types of enemies found in Borderlands: creatures, humans, and Guardians (aliens), all of whom can come in a badass version.

Guardians

 * Sera Guardian
 * Guardian Wraith
 * Principal Guardian
 * Arch Guardian
 * Guardian Spectre
 * Badass Guardian

Creatures

 * Scythid
 * Skag
 * Alpha Skag
 * Skag Pup
 * Rakk
 * Rakk Hive
 * Worker Spiderant
 * Soldier Spiderant
 * Gyro Spiderant
 * Aliens

Humans

 * Bandit
 * Crimson Lance
 * Midget Bandits
 * Bruiser
 * Psycho
 * Psycho Midget

Bosses

 * Nine Toes
 * Sledge
 * Skagzilla
 * Roid Rage Psycho
 * Mad Mel

Badasses/Badmuthas
Described by Randy Pitchford as "World of Warcraft has Elites, we have Badasses." Badasses are tougher variants of the creatures and humans. They can take and deal out more damage, but if you kill it, the rewards are great. However, if one starts a new game+, then badasses become "Badmuthas" and are twice as powerful as badasses and take much more time and skill to defeat.

Badass enemies, in addition to having "Badass" as part of their name, are also often distinguished by having glowing, blue eyes. Badass versions of creatures also gain an elemental attribute, such as a fire-breathing skag or a corrosive scythid that explodes for corrosive damage when it dies.