Grand Ossuary

-: Whenever a creature dies, distribute a number of +1/+1 counters equal to its power among any number of target creatures he or she controls.
-: Each player exiles all creatures he or she controls and puts X 1/1 green Saproling creature tokens onto the battlefield, (1/2)
-: (2/2) where X is the total power of the creatures he or she exiled this way. Then planeswalk.