The Great Forest

When The Great Forest enters the battlefield
sacrifice it unless you pay {1}{w}{g} plus {2} for each
time The Great Forest has left the battlefield.
{t}: Add {g} or {w}
{1}{g}{g}{t}: Create a 1/1 green plant creature token
with haste, then plants you control get +2/+1 until
end of turn.
The Great Forest can be your commander.