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Hydra Trainer

Creature — Human Warrior

You may exert this creature as it attacks. When you do, target creature gets +X/+X until end of turn, where X is the number of counters on permanents you control. (An exerted creature won't untap during your next untap step.) : Adapt 2. (If this creature has no +1/+1 counters on it, put two +1/+1 counters on it.)