One of the antagonists of Mahou Shoujo Lyrical Nanoha A's Portable: The Battle of Aces. Material-S, also known as Starlight Destroyer (星光の殲滅者 Hoshihikari no Senmetsusha) and Stern The Destructor (シュテル・ザ・デストラクター Shuteru za Desutorakutā) is a "dark copy" of Takamachi Nanoha. She wields Luciferion, a copy of Nanoha's Raising Heart.
In Mahou Shoujo Lyrical Nanoha INNOCENT, she is known as Stern Starks and her resemblance to Nanoha is merely coincidental.