The Endless Swarm

At the beginning of each upkeep, you control
more creatures any one of your opponents,
creatures you control get trample until end turn.
At the beginning of each upkeep, if you control
five or more creatures, creatures you control get
+1/+1 until end turn.
At the beginning of each upkeep, if you control
ten or more creatures, creatures you control get
+2/+2 until end turn.
It is as if nature itself wants you dead.