142 cards found matching energy cost is 3

Pit Crew
Poro Herder
Portal Rescue
Prepared Neophyte
Pyke, Dockside Butcher
Pyke, Returned
Ravenborn Tome
Rek'Sai, Breacher
Rengar, Pouncing
Ribbon Dancer
Right of Conquest
Royal Entourage
Scorchclaw
Sentinel Adept
Shadow
Sharkling
Shen, Kinkou
Shipyard Skulker
Skyfall of Areion
Sneaky Deckhand
Solari Shieldbearer
Solari Shrine
Sprite Call
Stand United