Charge-up Bomb

Suspend X - {x}{b/r}. X can't be 0. This card enters with X charge counters on it.
{t}: Place a charge counter on this card, then give control of it to an opponent. This ability costs {1} more to activate for every 2 charge counters on this card.
At the beggining of your end step, if this card has any charge counters on it, sacrifice it, then it deals 3 damage to you for every charge counter it had.