Screll, The Screeching Horror

Whenever a creature you control attacks put
a +1/+1 counter on target creature you control.
Whenever a creature with a +1/+1 counter dies,
you may move that creature's +1/+1 counters to another target creature.
{t}, Remove Screll, The Screeching Horror from
the game, then put "Eldrazi's Altar" from outside
the game on the battlefield tapped.