Eyeskull Spider

Final Strike - (Deathtouch. Creatures blocking or
being blocked by this creature gain First Strike).
Whenever a creature is killed by this creature and
would leave play, instead put it back into play under
your control with a -1/-1 counter on it, then
Eyeskull Spider becomes an aura enchantment
attached to the creature unless the creature leaves
play, then Eyeskull Spider becomes a creature again.

"It eats the head of people it kills and becomes the
new head for the corpse."