Twin Blood is an alternate version of Blade and Evil's first battle, with drastically different character and mecha designs from the rest of the series. Blade/D-Boy does not need Pegas to transform and the armor more closely resembles the Radam humanoids from Tekkaman Blade II.

In the year 2167, a wave of radiation released by the supernova of the nearby star Hydrus Beta caused cataclysmic damage on Earth, leaving millions dead. Now, it is the year 2356. United to rebuild Earth, humanity prepares for the supernova's second wave of destruction. In order to protect the planet from future harm, massive space colonies called Foundations have been built throughout the Solar System. Acting as centers for both knowledge and exploration, it is at one of these Foundations—the Stellvia—that Shima Katase applies to be a preparatory student against her mother's wishes, aspiring to see space directly with her own eyes. At the Stellvia, Katase trains to become a pilot and hopes to be selected for the Great Mission to shield Earth from the second wave. While she struggles with both her pilot classes and her tumultuous social life, she slowly grows into someone who might just be able to protect humanity.

The story is set in the year 2050 AD, and mankind has been steadily advancing its space technology. However, the planet is suddenly set upon by a mysterious enemy: the forces of Eldar, who came from 250 years in the future. In their time, 2300 AD, their planet Eldar was invaded by Earth, and soundly defeated by Earth's Trinity Energy, a mysterious energy used in their weaponry that possesses power many times that of a hydrogen bomb. The Eldar people's objective is to steal this Trinity Energy before it can be used against them. The Eldar forces begin by taking over Jupiter's moon Io, one of the places humanity has immigrated to by then. After that, they begin to attack Trinity City with their legions of Cosmosauruses in order to steal the Trinity Energy. Toshiya and his friends use God Sigma to protect the planet and the Trinity Energy, and the battle evolves into a long war to retake Io. (Source: Wikipedia)

After polluting their own planet beyond repair, a race of evil aliens target earth as their next home. Now it is up to a lone outcast and his robotic spacecraft, Baldios, to defend earth. But, first he must convince the distrusting human population of the impending danger. (Source: ANN)