Yavimaya Bloomsage // Channel

At the beginning of your end step, put a +1/+1 counter on target creature you control. Then if that creature has power 7 or greater, this creature becomes prepared. (While it's prepared, you may cast a copy of its spell. Doing so unprepares it.)
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Until end of turn, any time you could activate a mana ability, you may pay 1 life. If you do, add {C}.