Talk:Incubus/@comment-29602226-20170313202153/@comment-10429980-20170316001343

Looking young regardless of age is something that applies to all monsters, but they still die of old age. MGE volume 1 (which has a lot of undeads including the skeleton race) states in its general info on monsters: '''They have long life spans compared with humans. (It varies depending on race, from only a little longer than humans, to those who live for thousands of years.) No matter how old they get, their forms remain young and beautiful, and they never physically age any further than that.'''

Automatons were not originally monsters, or necessarily even living things. Plus they were dormant and lifeless for thousands of years, that's not the same as actually being alive and active for all that time.

The thing about magical material monsters is that they have become "living" in many senses thanks to magic. So depending on how said magic works they may well be able to "die" of old age too.

But basically until we get further word on it all we have about lifespan of monsters is that general info quoted earlier that implies no monster is truly immortal (unless one counts the soul of course, but KC has stated there is a system of reincarnation for them as well).