Time-Cloud Mist

Delay X - {x}{x}{w/u} (You may cast this spell for {x}{x}{w/u}. If you do, exile it as it resolves with X
time counters on it. At the beginning of your upkeep,
remove a time counter. When the last is removed,
return it to your hand.)
Tap X creatures you control.
Whenever you remove a time counter from
Time-Cloud Mist, exile target creature.