Nagash, Lord of the Undead

Flying, fear, undying, convoke
When Nagash enters the battlefield or attacks,
flip a coin. If you win the flip, destroy target
creature you don't control. If you lose the flip,
remove all counters from Nagash.
Whenever a creature an opponent controls dies,
its owner may pay life equal to its mana value.
If they don't, put it onto the battlefield under
your control tapped.