|Game||Tales of Hearts|
|Japanese Voice Actor||Tomoko Kaneda|
|Character Designer||Mutsumi Inomata|
Corundum is introduced in the story after Mysticete's rebirth, when Creed restores her functionality, alongside Chlorseraph. Energetic and analytical, she often twirls, speaks rapidly, and giggles while taunting the protagonists and spewing her programmed observations. Creed eventually uses her to power Mysticete, which causes her tremendous pain. Lithia Spodumene later frees her from this captivity and talks her back to her true self, Creed having manipulated her Spiria to fulfill his own goals, all the while ignoring her agony.
No longer posing a threat to the group, she works toward activating the teleporter to transport them to Gardenia. If spoken to after the path to Gardenia has been opened, Corundum will allow the group to Spiria Link with her to determine the cause of her longing for Lithia's well-being. She ultimately discovers that she possesses non-programmed feelings, allowing her to experience the surface of emotion despite her artificial Spiria. After this event, Corundum gives the group the "Drill Ribbon" equipment item, which resembles her own blond locks.
Appearance and Personality
Corundum appears as a young girl with violet eyes and blond hair fashioned into two curled pigtails. She wears a yellow, plated coat adorned with a red jewel in the center and a black tiara with a purple jewel on her head. As a Joker-type mechanoid, Corundum is designed more for practical use and data-gathering rather than battle. She is obsessed with gathering information and is driven more by curiosity than anything else.
- Corundum derives from the mineral of the same name.