It also doesn’t have to be dialogue. It could just be flavor text. When you land the killing blow on a creature you might get -
The zombie slumps to the ground, lifeless.
or
Attempting to take another step, the wolf collapses.
Flavor text can make good games great and it wouldn’t be hard to churn out several dozen strings of text that would apply to any creature, as well as the additional few for specific creature types (like the broken cyborg). I’d love to see a Mi-go go down screaming angry pseudo-sentences.