Genre breaks are design flaws that allow objects that break the immersive quality of the game(e.g. "FPS inside RPG"), forcing players to reevaluate the game genre.

1.Visual genre break:Clash with the game aesthetics:e.g. having vastly different design or theme from the game world default.
2.Anachronism:Conflict with the game setting:e.g. medieval fantasy with laserguns(often disguised as spells).
3.Subverts Mechanics expected of the genre :Clash with combat mechanics of the genre:e.g. mounted cannons, guns vs archers(i.e. changes the combat in favor of item/object)
4.Misfit item:Clash with character design:e.g. unrealistic proportions or misfit equipment.
5.Unrealistic properties:Provide unrealistic(for the genre) stats, buffs/effects not expected from item/monster/object in the genre.
6.Language break:Terms and language that is disconnected from the game setting/genre.

The problem is often subtle and only affects player who encounter the objects: nevertheless it has potential to ruin the game integrity and reputation via memetic/viral spread(especially if game genre is serious).