Tuffnut, Shaper of Flesh

+1: Target creature gains two Metamorphosis tokens. On that player's end step, remove one. When none remain, creature becomes a 1/1 green/blue frog.
-3: Put {x} +1/+1 tokens on all frog creatures where {x} is the number of frog permanents on the battlefield.
-7: Gain control of all frog permanents.