The Assist (アシスト, Ashisuto?) system is a battle mechanic in Star Ocean: Anamnesis. In it, the players can use characters they own to provide support to party members through two functions: Assist Skills and Rush Assists.
A character must be level 70 to be used as an Assist, and as such, only 6☆ units are eligible; some collaboration characters, however, cannot be used as Assists. Equipping an Assist can be done on the "Change Gear and Skills" option on the Characters menu.
The Assist Skill (アシストスキル?) function can be controlled, and is activated via holding the Assist button that appears during battle. There is also a option in the settings that allows the player to be able to tap it and activate it. In any case, a character's Assist skills is generally the same as their Rush Mode additional effect. Revive effects—like Evelysse or Ioshua's—are removed or changed to another effect. The strength of an Assist skill depends on the unit's Limit Break: for the full effect which indicated as being LV 2, the character needs to be maxed out.
The second feature, Rush Assist (ラッシュアシスト?), is randomly activated when a character with an Assist equipped starts their Rush Mode. This will increase their Rush Combo Bonus depending on which stage the party is at, and whether or not the Assist character is fully Limit Broken. If maxed, the bonus changes to the following values: 50% ￫ 150%, 100% ￫ 200%, 150% ￫ 250%, 300% ￫ 400%. While it is a random chance for a Rush Assist to happen, the odds increase if the character has a high Friendship level.