This other-worldy creature of immense proportions is the true appearance of the mysterious Grandmaster Meio. Meio Prime has a massive round body encased in a larger shell-like bony exterior with spikes coming out from the top. The main body appears scaly and has a single, slit eye in its upper area with four yellow spikes protruding right below it. The lower half of his body shows a large set of dark blue arms clutched together, each wearing several gold rings, and in the center stands Meio's human form merged as part of the body. Meio Prime also has four small wings and two long, one-eyed dragon-like limbs coming from large holes in the back of the shell. As Grandmaster Meio always operates in his human visage, his real appearance has been concealed from the inhabitants of Earth, and not even his own subordinates have ever seen it. As everything about him is enshrouded in mystery, nobody knows with certainty just from where did the existence known as Meio came from, or for what purpose he exists.
Grandmaster Meio was forced into revealing his true form after being defeated by Hiryu. Injured during their confrontation, Grandmaster Meio retreats through a portal to his station, The Third Moon, in Earth's orbit and reveals his true self. In pursuit of his target, Hiryu arrives at the remains of the station with the imponent Meio Prime awaiting him. Losing his confident and arrogant attitude, Meio Prime violently lashes out against Hiryu in an attempt to kill him while screaming that he'll create his perfect race.
Meio Prime unleashes the full extent of his powers, but Hiryu manages to survive the assault and finally brings the creature down. Defeated, Meio Prime falls toward Earth with Hiryu standing on his top as Meio's body slowly disintegrates upon atmospheric entry.
In his true form, Grandmaster Meio's abilities are increased exponentially, allowing him to summon and release stronger projectiles in massive numbers. As Meio Prime, he's said to gain the ability to control gravity at will, and can generate projections of psychic energy with its dark blue arms: the upper ones can generate fire-based projectiles and the lower ones can project blasts of energy. He can also unleash a powerful electric beam and makes use of his dragon "arms" to attack from a distance.
Hiryu confronts Meio Prime in a large area formed by a circle of metal junk floating in space around a number of Gravitron units, serving both as platforms and cover from any attack. Meio Prime stands in the background and attacks Hiryu, only retreating when he receives enough damage in order to use his dragon limbs. Meio Prime's only weakpoint is the human face in the center of the body, which can be reached by performing Plasma Catapults off one of the Plasma Rings floating nearby. As the battle goes on, Meio Prime starts mixing together his attacks and attacking more often.
- Fire Wheel: Meio Prime's upper arms generate a large red orb between them, and from there releases a spinning array formed by rows of three fireballs. This attack can move to either direction, but the fireballs can be easily reflected by the Cypher.
- Fire Star: Meio Prime's upper arms generate the fire orb, then unleash a stream of fireballs at five different directions. The easiest attack to dodge.
- Fire Rain: Meio Prime's upper arms generate the fire orb, and from there radiate thousands of fireballs at all directions. The fireballs can be reflected as well.
- Energy Blast: Meio's lower arms generate a large blue orb between them, and from there shoots three small blasts of energy at Hiryu's direction. When hitting a surface/Gravitron, these blasts unleashes two pulses that run across said surface.
- Lightning Beam; Meio shoots a large, powerful electric strike from the eye in his body. This beam moves at either direction and can reach across the whole room, so it can only be avoided by quickly hiding behind a Gravitron.
- Dragon Limbs: When receiving enough damage, Meio Prime retreats further into the background and lets his dragon limbs attack. The limbs attack Hiryu by striking at his position three or four times, each strike releasing blasts of energy around them and through the surface they hit. The last strike always leaves the limb stuck in place, opening it to attacks for a few seconds. When damaged enough, the limb will be knocked out temporarily.
Meio Prime's concept and general design are a clear reference to Caduceus, the final boss from Strider 2, both being large space monsters with similar bizarre designs. Making this more apparent, Meio Prime's official art uses a similar background to the one in Caduceus' official art, and both end up burning away during atmospheric entry after defeat.
While the English script directly refers to Meio Prime as a "space alien", the Japanese script instead remains ambiguous about his actual origins and status.
- Capcom (February 2014, multi). Strider Hiryu (Japanese). Character Intel #39: Meio Prime
- Capcom (February 2014, multi). Strider (English). Character Intel #39: Meio Prime