Zhaitan

Flying
This creature's attack is equal to the amount of
undead creatures you control.
When Zhaitan enters the battlefield, move all
nonlegendary creatures you control to the
graveyard.
Whenever a nontoken non-'dragon minion'
moves to the graveyard, you may create a token
copy of the creature. It also has 'undead dragon
minion' as a creature type.