That’s probably why you only saw him once. It’s easy to get him to pop out of one of the four midget boxes in the WEP, but he is incredibly rare anywhere else. Maybe it’s because every time the game decides to spawn a robot midget it has a chance of being Jimmy, and robot midgets are pretty commonplace there. I actually completed the Jenkins challenge three times already just by farming those four little boxes.
Getting back on topic, why don’t we make a list of those enemies? I just remembered a few others, but I’m leaving regular farmable bosses that are linked to mission objectives out of it. On to the list:
Friendly NPCs
- Michael Mamaril
Tubbies
- Tubby Skag
- Tubby Spiderant
- Tubby Stalker
- Tubby Varkid
- Tubby Rakk
- Tubby Midget
- Tubby Bones
Unique enemies that spawn randomly
- Muscles
- Jimmy Jenkins
- King Mong
- Donkey Mong
- Pimon
- Tumbaa
- Black Queen
- Mr. Bubbles
- Lil’ Sis
- Spiderpants
Unique enemies that are always at their spawn points
These aren’t rare at all, but they aren’t linked to any missions and the game never points them out for you.
- Mad Mike
- Son of Mothrakk
- Rakkman
- Savage Lee
- Bonehead 2.0
- Creeper/Badass Creeper
- Geary
- Warlord Slog
Unique enemies you get through evolving other types of enemies
- Vermivorous
- God-Liath
- Iron God
- King of the Orcs
- Omnd-Omnd-Ohk
Secret raid bosses
- Dexiduous
Legendary Loot Midget types
- Legendary Loot Midget Marauder
- Legendary Loot Midget Rat
- Legendary Loot Midget Nomad
- Legendary Loot Midget Psycho
- Legendary Loot Midget Goliath
- Legendary Loot Midget Engineer
- Legendary Loot Midget Combat Engineer
- Legendary Loot Wee Gun Loader
- Legendary Loot Wee Jet Loader
- Legendary Loot Wee War Loader
I think these are all the unique enemies in the game. If you see any mistakes, omissions or have anything to add, let me know and I’ll update the list.

