Ys vs. Trails in the Sky: Alternative Saga has an anti-piracy feature activated if the game detects the PlayStation Portable's system firmware is illegitimate. During a match, the collisions for walls and some floors will be turned off at random points, occasionally causing players to clip through walls or fall out of bounds before respawning back at the starting location. Additionally, some bosses and enemies will not respawn if they fall off the map, making fights with them unwinnable.