The games are designed to keep people trapped. There was a mirror "game" where the more you go through them the more monstrous you look.
Full Tilt (2003) by Neal Shusterman...?
Sixteen-year-old Blake and his younger brother, Quinn, are exact opposites. Blake is the responsible member of the family. He constantly has to keep an eye on the fearless Quinn, whose thrill-seeking sometimes goes too far. But the stakes get higher when Blake has to chase Quinn into a bizarre phantom carnival that traps its customers forever.
In order to escape, Blake must survive seven deadly rides by dawn, each of which represents a deep, personal fear -- from a carousel of stampeding animals to a hall of mirrors that changes people into their deformed reflections. Blake ultimately has to face up to a horrible secret from his own past to save himself and his brother -- that is, if the carnival doesn't claim their souls first!
From a reader review:
The main plot revolves around a kid named Blake, who is going off to college at an Ivy League school. When he goes out with his friends, he meets an irresistable girl named Cassandra, who promises great thrills at her theme park. Strangely enough, one of Blake's friends says that the park appears to never be in the same location twice. He finds when he enters the park that he must ride seven rides that represent his greatest fears (in several hours, no less) in order to escape the park alive. Will he pull through?