Xexyz
About
Xexyz (pronounced zeks'-zees/zeks'-iz), known in Japan as Kame no Ongaeshi - Urashima Densetsu (亀の恩返し〜ウラシマ伝説〜, Turtle's Replayment: Urashima Legend), is a 1988 video game published by Hudson Soft for the Nintendo Entertainment System. The game was released in Japan on August 26, 1988, and saw a North American release sometime in April, 1990. The game was never released in Europe.
The story takes place in the post-apocalyptic year of 2777, after Earth has been devastated by nuclear war and natural disasters, with the island nation of Xexyz being now threatened by alien robots.