Instead of one description for enemies, a generator could be loaded with friendly description sentences to randomly cobble descriptions together for the undead enemies… Stuff like:
Its arm is dangling by a thread.
A large shard of glass impales its torso.
Its jaw is broken and dangling freely.
One of its eyes are ruptured.
One hand has been gnawed off.
Its hair has been mostly singed away.
Its head lolls sideways from a broken neck.
Its intestines trail along behind it.
Its movement is erratic due to a broken leg.
Its clothing is blood-soaked and shredded.
Its wounds crawl with maggots.
It leers at you though it has no eyes.
It moans gurgle through a hole in its throat.
It has a massive laceration along its torso.
It drips clots of blood steadily.
Its teeth chatter together as it walks.
Its face is furrowed with claw marks.
Its back has been gnawed in various places.
A piece of bloody rope dangles from its wrist.
A shoe has been lost during its travels.
A pair of broken glasses perch crookedly on its smashed nose.
A partially destroyed heart tattoo can be seen on its mangled bicep.
Thick ribbons of skin hang wetly from its flayed torso.
It is pierced by multiple shards of blackened shrapnel.
A thick cloud of buzzing flies swarms around it.
It drags along its nearly severed foot.
It violently chews an unidentifiable chunk of meat.
Its torso has been consumed down to the bone.
It lurches forward with its arms outstretched.
It jerks its head randomly side to side.
Its tongue hangs slack from a hole in its cheek.
Its eyes appear to have no pupils.
Its hair is matted with chunks of gore.
A lung hangs freely from a massive chest wound.
Things of that nature 
Dunno if it’d ever be added, but you could feel free to add your own here if compelled…
