Blending traditional role-playing elements and fast-paced action, Hellgate: London plays much like a spiritual successor to Blizzard Entertainment’s Diablo.​

Lead Designer Bill Roper describes the game as an evolution of action role-playing. At the core of Hellgate: London, he explains, are the concepts of randomization, rarity, and customization. ... While we’re concerned that randomization may prove frustrating since levels will constantly be changing and enemies always respawning, Hellgate: London appears to use this to create an effervescent gameplay experience that is always new, different.​