Tenchi Muyo! War on Geminar

Isekai no Seikishi Monogatari

Kenshi —half-brother of intergalactic hero Tenchi Masaki— has been summoned to the mysterious world of Geminar, and his only hope of returning to Earth is piloting a bio-mechanical weapon in a shocking assassination attempt! When the mission fails and Kenshi is captured, he discovers he's been lied to by the very culprits who transported him to this strange new worl...