If Illidan Stormrage is played when the enemy hero is Malfurion, Illidan says "hello, brother"
Although the game is set in the World of Warcraft universe, many cards and characters are unique to Hearthstone. These range from the entirely new Arch-Thief Rafaam, an Ethereal grave robber and the main villain of the 'League of Explorers' Adventure, to the significantly altered Ragnaros, Lightlord, a redeemed take on the infamous corrupted Firelord. Normal Ragnaros and many other staple World of Warcraft characters also feature ingame.
The Tortollans, a race of small humanoid turtles, were created by the Hearthstone team for the jungle-themed 'Journey to Un'Goro' expansion. They were later featured in World of Warcraft's 'Battle for Azeroth' expansion, making the Tortollans the first race to be invented by Hearthstone and included in World of Warcraft.