I consider aberrations to be extra-terrestrial beings. In my game, these beings are the trolls who are there to kill anything in their path. However, I wanted to add a somewhat hidden mechanic that's an aberration (A deviation in the normal structure), so I decided that every time the player dies, they get resurrected with what seems a full health bar, but it's actually halved from the original. So every time they die, their health is halved until they are one hit from dying. Although the resurrections are not infinite, you only get 3 :)