Grump has been performed by Arin Hanson since the show's debut on July 18, 2012, even though Not-So-Grump was initially played by Jon Jafari until he remaining the demonstrate on June 25, 2013, at which stage he was replaced by Leigh Daniel "Danny" Avidan, a.k.a. Game Grumps debut on a Grumpcade replay of BurgerTime.