This is a table top collectible card game and has no connection to the World of Warcraft MMORPG other than the name of the game and the theme. This is not a sale of any of Blizzard Entertainment's intellectual property associated with the Video Game. To be clear, no in game property for the World of Warcraft is being sold.
This and other Murloc allies you control have Protector. (They may exhaust to become the defender when an opposing hero or ally attacks.)