The Thiima is the villainous force from G-Darius. They are a mechanical alien race that exists for the sole purpose of protecting the peace in the entire universe, staying dormant in a different dimension.
The inhabitants of the planet Amnelia, a very advanced civilization, waged a long war against planet Blazar, whom Amnelians had been fighting over jurisdiction over the moon Mahsah. To put an end to the war, they created the Mass Destruction weapon A.N. (All Nothing), the use of this weapon ended with the destruction of Blazar. This prompted the awakening of the Thiima, which sensed Amnelia as a threat to the peace in the universe, immediately attacking Amnelia and easily crushing their resistance. The Amnelian managed to get a piece of a Thiima battleship and, using it's technology, they created the Silver Hawk, a spacecraft capable of wielding multiple weapons. Two pilots are sent to fight the Thiima, tracking them to their origin, a planet that later became known as Darius. The two pilots, Sameluck Raida and Lutia Feen, were sent to destroy the Thiima, but a portion of a Thiima battleship is retrieved by a malevolent army known as Belser, which used their forbidden technology on it's own battleships.