Soul Splicer

At the beginning of your upkeep you may put a charge counter on Soul Splicer.
{t}: Exile a creature you control, then a creature you don't control with converted mana cost equal to the amount of charge counters on Soul Splicer.
{t}, sacrifice Soul Splicer: Choose two creature cards exiled with Soul Splicer. Put a copy of one of those cards with a number of +1/+1 counters on it equal to the power of the other card onto the battlefield.