Fickle Forcemage

When Fickle Forcemage enters the battlefield, if it's your turn, put two +1/+1 counters on it. If it's not your turn, Fickle Forcemage gets +3/+3 until end of turn.
Stalk {2}{g}{g} (At the end of each block step, if there is an unblocked creature attacking you,
you may cast this card for its stalk cost. If you
do, choose an unblocked creature attacking you. This creature blocks that creature.)