Limit Break (限界突破, Genkai Toppa?), abbreviated LB, is a gameplay feature in Star Ocean: Anamnesis that pertains to characters, weapons and accessories, and allows them to improve their stats by making the most of possible duplicates.
Characters, when Limit Broken, improve all of their base stats—HP, ATK, INT, DEF, HIT, GRD—but the number of times this can happen depends on the character's base rarity: 3☆ characters are maxed out at three times, 4☆ characters at five, and 5☆ characters (both ACE and non-ACE) are maxed after ten times.
When a player obtains a character they already own, the duplicate will be automatically synthesized into the original and Limit Break it by 1. If the character has already reached the maximum number of Limit Breaks, the player instead obtains Limit Break materials according to the characters' rarity—3☆ characters are converted into a S. Limit Breaker, 4☆ characters give a M. Limit Breaker, and 5☆ units become a L. Limit Breaker. These are used to perform Limit Breaks on rarer units in the Character menu by spending FOL and the appropiate materials. Players can select any of the three Limit Breaker types for the process, e.g. for a 5☆ character, they can choose either two Large ones, or ten Medium, or 50 Small. Whichever the choice, they will Limit Break the selected character by 1.
Conversely, Limit Breaking weapon and accessories is invariably performed at the Items menu on the Enhance (武器・アクセサリー強化?) option. It is done by synthesizing two or more of the same item or, in the case of some weapons, with uncapping materials (usually in the form of special Hammers). Limit Breaking increases their level cap by 2 up to a maximum of five times. In other words, they start with a Level 10 cap, and they can be upgraded up to Level 20. Because of this, the process may sometimes simply be called "uncapping". On 5☆ weapons, it also may reveal hidden factors, which usually happens at LB 5.
Synthesizing non-identical weapons will only give Enhancement points to the base weapon, which causes it to level up every 10,000 points and thus gain new stats. Limit Breaking always raises a weapon's level by 1.