Grim Tomb Recurrence

Whenever a non-token Zombie creature you control dies, you may exile it. If you do, create a 1/1 black Skeleton creature token.
Whenever a Skeleton creature token you control dies, create a 1/1 white Spirit creature token with flying.
"You may have won this battle, but pray you have strength left in you, for now comes the next."
-Liliana Vess