Erementar Gerad Play as Glad
Successfully complete Story mode on the Hard difficulty setting to unlock Glad.
Play as Viro
Successfully complete Story mode on the Normal difficulty setting to unlock Viro.
Third costume
Successfully complete Arcade mode with any character to unlock their third costume set, which is either a variation of that character or having the ability to play as their partner.
The image featured at the top of this post is ©The Legend of Heroes: Trails of Cold Steel III key art / Original