Ovir Kan, Growing Void

If Ovir Kan, Growing Void would leave the battlefield, exile target creature instead. When a
creature is exiled this way, put a coercion counter
on that creature.
At the beginning of your end step, return a
creature from exile with a coercion counter on it
to the battlefield under your control. Return two
creatures instead if four or more creatures in exile
have coercion counters.