Guilty Gear XX is the main title in the Guilty Gear fighting game series, known for its fast-paced 2D combat, distinctive heavy-metal aesthetic, and roster of unique characters. It introduced an expanded version of the Guilty Gear formula with new mechanics and balance changes, and later received several updated editions and revisions. The series is especially popular in competitive fighting game communities and is often referenced by its base title rather than its many version-specific subtitles.