Submachine: Legacy asks a lot of the player: a lot of attention, a lot of time, a lot of thought, and a lot of travel. In return, though, it has an incredible amount to offer. The narrative is both intriguing and unobtrusive, allowing you to take or leave as much as you want while you get down to puzzle-solving. The puzzles themselves are almost uniformly excellent, while the art and music are perfectly suited to the aura of mysterious foreboding that infuses each chapter. This is not a game to be approached casually or without the full complement of one’s faculties, but the subnet contains such an embarrassment of adventuring riches that it’s no surprise people have spent so many years jumping at the chance to vanish there.