ソーナと小(こ)枝(えだ)ッ歯(ぱ)

Thorna and Twigtooth enters with two −1/-1 counters on it.

Whenever Thorna and Twigtooth attacks, remove all counters from target creature you control. Each opponent loses X life, you gain X life, and the topmost creature card in your library perpetually gets +X/+X, where X is the number of counters removed this way.