Megamoeba, Ultimate Lifeform

Indestructible, trample.
Whenever Megamoeba deals damage to a creature, exile that creature and put X +1/+1 counters on Megamoeba, where X is that creature's toughness.
Exile a creature you control, or a creature in your graveyard or hand: Put X +1/+1 counters on Megamoeba, where X is that creature's toughness.
Whenever Megamoeba deals damage to a player,
exile a creature from that players graveyard, and
put X +1/+1 counters on Megamoeba, where X
is that creature's toughness.