Rekka and his crew don't save the world, they just show up every week to crush whatever crawled out of the ground this time. The Gaist themselves are the real draw: each one feels like a distinct threat with its own logic, its own weak point, its own reason to exist. You're not watching a story about destiny or chosen ones. You're watching four kids in powered suits figure out how to survive the next creature, and somehow that's enough.

In 2047, humanity finds Gaimetal, an ore packed with pure energy, some 50,000 meters below the surface, and mining soon spreads around the world. In 2055, the Gaist appear: metal-bodied creatures covered in Gaimetal that start attacking people. To answer the threat, the Gaist Crusher Garrison, or GCG, is formed. By 2064, Rekka, Hayato, Kurama and Siren are among the fighters who don Gaist Gear, armor made from Gaimetal, to take on more than a hundred kinds of Gaist. They also face a mysterious group called the Erasers. The result is an action fantasy built around armored heroes and supernatural metal monsters.