River Wardens

Impart--{g/u}, Return two lands you control to
their owners' hand. (You may cast this spell for its
impart cost. If you do, as this creature enters the battlefield, if it's not a token, you or your teammate
may create a token that's a copy of it.)
Whenever River Wardens blocks or becomes
blocked by a creature, that creature gets -X/-0
until end of turn, where X is the number of
Frogs your team controls.