Tharizdun, the Ender

At the beginning of your upkeep, for each
opponent, choose a permanent that opponent controls. That player sacrifices that permanent.
If Tharizdun would leave the battlefield, flip a
coin. If you win the flip, Tharizdun returns to
the battlefield under it's owner's control. If you
lose the flip, exile Tharizdun.
Chained no longer.