|The main characters (pretty much Saint Seiya on horses)
A shonen manga by Masami Kurumada (the mangaka of Saint Seiya). Its story centers around Teppei, who races to rescue his scientist brother from the clutches of the evil Machine Empire. He's helped in his quest by X, a Pegasus-shaped B't (Empire-created AI-equipped mechas that bond with their pilots through their blood and have unique abilities each) that was formerly considered the strongest B't before he got discarded as trash only to be revived by Teppei's blood years later. Teppei also wields the Messiah Fist, a weapon given to him by a renegade former Empire officer who also trained him in combat. Teppei has to make his way through the Empire's forces and their own B'ts (some of which join his cause for their own reasons), while others uncover the truth behind the Machine Emperor's centuries-in-the-making ultimate weapon.
Powerwise, B't X is above the likes of HST as even nameless Empire mooks can outfit their (hypersonic) B't rides with nukes and shield themselves from the radiation, and their squads of high-ranking officers include Gai, a neutrino Logia that can't be harmed by conventional means and can spam copies of himself, Meimu who can induce sleep and kill people inside nightmares of his own creation, musical assassins Fao and Salome, killer clown Juggler who can make people's heads spin until they are ripped from their bodies, people who can turn their enemies into stone or jewels, mad genius Poe who can banish people to another dimension, and creepy child Misha who can make people's heads explode with telekinesis from a distance (ala Darth Vader). Their defense systems can also protect them from sea pressures, volcano temperatures, armor-melting acid, being blasted into orbit and the void of outer space. Finally, apocalyptic B't Raphael requires planetbusting power to be destroyed.
Some could call this series a sci-fi Saint Seiya, especially since Kurumada's fondness for the Tezuka star system makes several characters expies from his other works.