According to Matt Barton, the game Telengard, released by Avalon Hill in 1982, influenced the development of Diablo.
At first, Diablo was a turn-based role-playing game, but later in development, also influenced by the previous success of Warcraft: Orcs & Humans, they decided to make it a real-time action game. The game was also originally conceived to be made in claymation (much like ClayFighter), but they decided to have a 3D isometric style instead.
players: single player, multiplayer (Internet, LAN / local, Modem, co-op, same or split screen)
input: keyboard, mouse
popularity: above average