Champions of the Shoal (Lorwyn Eclipsed #356)

Creature — Merfolk Soldier - {3}{U}
As an additional cost to cast this spell, behold a Merfolk and exile it. (Exile a Merfolk you control or a Merfolk card from your hand.)
Whenever this creature enters or becomes tapped, tap up to one target creature and put a stun counter on it.
When this creature leaves the battlefield, return the exiled card to its owner's hand.
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