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Defend, also called Guard, is a battle command used by all player characters and some enemies. Upon using the command, the character will defend themselves from enemy attacks, reducing the damage they take on the current turn only. Like Attack, it cost no Skill Points to use.
While no icon is displayed with the command, Defend does have an icon internally in the games. In Power Master: A Strange Journey MV, the icon is a shield that is also used for similar commands, like Cover.