Phantasos — Robert Barnard

A mysterious new game has appeared in arcades across the Pacific Northwest. It's called Phantasos, and it promises a state-of-the-art virtual reality experience. There's only one problem: everyone who plays Phantasos inevitably falls victim to bizarre nightmares, dark hallucinations, and a string of very, very bad luck. Are these delusions all in the player's mind? Or did something start to follow them the day they played Phantasos?