Fallout 3 creatures

This is a list of all creatures known to appear in Fallout 3:

Humanoids

 * Human
 * Ghouls (sentient): Ghoul, Chinese Remnant
 * Ghouls (feral): Feral Ghoul, Ghoul Roamer, Glowing One
 * Super Mutants: Super Mutant, Brute, Master, Behemoth
 * Mirelurks: Mirelurk, Mirelurk Hunter, Mirelurk King, NukaLurk

Animals

 * Brahmin
 * Centaur
 * Deathclaw
 * Mole Rat
 * Yao Guai
 * Dogs: Vicious Dog, Raider Guard Dog, Scavenger's Dog, Talon Company Guard Dog

Insects/Bugs

 * Giant Ants: Giant Worker Ant, Giant Soldier Ant, Giant Ant Queen
 * Fire Ants: Fire Ant Worker, Fire Ant Soldier, Fire Ant Warrior, Fire Ant Nest Protector, Marigold Ant Queen
 * Bloatfly
 * Radroach
 * Radscorpion, Giant Radscorpion

Robots
Robots are not exactly creatures, but can be as much of a threat to your character (if not more). It appears robots have a weakness to laser weapons.
 * Eyebot
 * Mister Gutsy
 * Mister Handy
 * Protectron
 * Robobrain
 * Sentry Bot
 * Automated Turret