Echo, the Hybrid

+3: Gain life equal to the number of creatures on the battlefield.
-3: Echo, the Hybrid becomes an X*/X* devoid creature, still a planeswalker, with indestructible, until end of turn. *# of creatures in graveyard.
0: Put 8 2/2 Eldrazi Scion on the battlefield where X is number of creatures in your graveyard. Transform Echo.