18. Resident Evil
In a word: zombies. Big, beautiful zombies with hyper-detailed ribbons of flesh dangling off their leering, glassy-eyed faces as they lurch forward to clutch at your throat. In 2002, Resident Evil was the best-looking game to appear on any platform, ever, pumping out a level of in-game detail that we'd previously seen only in pre-rendered cutscenes. It made the zombies and monsters of the PS original look like Muppets, and it was terrifying.
Resident Evil on the Cube is more than just a visual upgrade, though. It also adds new environments, a whole new subplot, and plenty of new scares to the simple horror story about paramilitary agents stuck in a haunted house. These include (but aren't limited to) a swarm of giant undead sharks, an Evil Dead-style cabin-in-the-woods scenario, and zombies that get up, turn red, and chase you if you don't stomp their heads in properly. This one hit relatively early in the Cube's life cycle, but it still stands as one of the creepiest horror games ever made.