Gaist Crusher(2013)

Gaist Crusher is a science fiction anime series set in a future where the discovery of Gaimetal, a high-energy metallic mineral, triggers an unexpected threat. In 2055, Gaist—metallic life forms composed entirely of Gaimetal—emerge and begin attacking humanity. By 2064, a specialized team of warriors known as Gear Gaist rises to combat the threat. Rekka, Hayato, Kurama, and Siren lead the charge against over 100 varieties of Gaist creatures in intense battles for survival. The series follows their fight to protect humanity from these otherworldly metallic invaders in a world transformed by technological discovery and extraterrestrial danger.