Altar of the Mighty

As Altar of the Mighty enters the battlefield, you
may sacrifice any number of creatures with
power 4 or greater. Altar of the Mighty enters
the battlefield with a charge counter for each
creature sacrificed this way.
Creatures you control enter the battlefield with a
+1/+1 counter for each charge counter on Altar
of the Mighty.
Where the strong seek power, they find only sacrifice.