Ratmen are half-men, half-rat, beastmen.
"Out of deep places of foul magic, a tribe of giant, upright rats emerged. Crude though their weapon and armor may be, many an adventurer, deep in a dungeon, has found himself suddenly ringed by a sea of red, hungry eyes and dully glinting swords."
Recommended resistances: Damage, Slow, Poison
Notes: the Ratmen are not strong but will gain strength in numbers. There is also a Plague Spreader Ratmen which is kind of Shaman. He has the ability Plague which cause unit to take damage over-time and moves to another enemy unit. Beware of using pets against them.