Rat
From Warhammer 40k - Lexicanum
Rats, also known under their scientific name Rattus Rattus, are animals found all over the Imperium. Spread from Terra by being transported onboard human spaceships, it has been joked about that the Imperium was forged by rats and humanity was just along for the ride.[1]
On some planets where they have been accidentally imported, rats have overwhelmed all other lifeforms, while on other worlds, they had interbred and created monsters.[1]
Sources
- 1: Traitor General (Novel) — The Lost (Omnibus), Chapter One
