ActionTrip:
Although visuals will be this game's forte, Hellgate: London promises to offer us quite enough food to chew on apart from that. The game does play in a linear fashion, but we are not to expect Diablo-like linearity. You will be forced to follow a certain path, but it's the random sidequests, as well as different monster and loot locations, which will make every single gaming experience differ. Randomly generated landscapes and paths, as in Diablo II, should serve for making the game more interesting and adding to its replay value. Roper insists a great deal of randomization will be included in the game, and while the quests will follow the main storyline or be directly involved in the story they should be complex enough to provide you with a unique experience every time. Choosing specific quests may take you to different paths, leading to different outcomes. Simple quests that will include going from point A to point B in order to fetch something for somebody won't be an option​

CVG:
According to the reports, the main storyline is mission-driven and branching, which hints at multiple endings, and sub-/random missions that extend the life of the single-player part of the game will additionally be present. Expect to be battling both above and below London ground - all looking pleasingly post-apocalyptic we're sure - employing... Yes of course, kick-ass firepower!​

Gaming Age:
Hellgate: London combines the depth of role-playing games and action of first-person titles, while offering infinite playability with randomly created levels, items, and events. The player creates a heroic character, completes quests, and battles through innumerable hordes of demons to advance through experience levels and branching skill paths.​