Fire Rain to find an action that can destroy Stout Shark in a single card. Aside from Velken Shock Troop (sometimes) and Adept Mage (sometimes), the only 3 energy-cost card that can make that claim is Captain Larlord (who at 2AP/3HP is a bit underwhelming offensively). No other 3 energy-cost card can make that claim!
Strong against: midrange and aggro decks.
Weak against: Ramp decks and green decks.