Posted August 14, 2011
Diablo changed enough things that I think it can be seen as having invented a new type of gameplay. It borrowed a randomized dungeon and combat-heavy gameplay from Rogue and its ilk, but the real-time gameplay was a huge change that sets Diablo apart from those games. Roguelikes are generally very strategic affairs that require careful planning, and they're also known for being extremely difficult to finish and for featuring permanent death. By moving to a real-time system, Diablo shifted its focus to fast-paced action and considerably lowered the difficulty, resulting in a game that plays very differently from a roguelike. I wouldn't call Diablo a roguelike although I will admit it was inspired by them.