Staff of eternity

When this enters play exile target creature you control.
{2}{t} This deals X damage to each target where X is the creatures power. If BBB is exiled under this, do it to every target except your life. Put on waiting counter on this
Whenever a creature is exiled you gain 5 life and untap this.
Each end step if this has 5 or more waiting counters on it, sacrifice it at the next combat.
"I GOT IT"