Aerover

Tells about a future where drones are common. Drones have played an indispensable and important function in human life. One day, a large meteorite fell on earth, and scientists discovered that it had an infinite source of energy, the "Cosmo Stone", and applied it to a drone, what people call a "space drone." One day, drone wars around the world broke out, and space drones were active as a weapon of war. As the damage spreads, world leaders proposed a ceasefire and sought to turn drones into symbols of peace, not weapons of war anymore. The result is the "Aerover Championship". (Source: MyAnimeList)