Sieve of Unbirth

Whenever a creature would be put into the graveyard from play, exile that creature.
Put X time counters on it. If it doesn't have suspend, it gains Suspend. (At the beginning of your upkeep, remove a time counter from that card. When the last is removed, cast it without paying its mana cost. If it's a creature, it has haste.) X is equal to the creature's converted mana cost.