Io Mikura (御蔵 イオ Mikura Io) is the protagonist of 2008 - 2010 manga series Mega Monster Battle: Ultra Adventure, 50 years after the events of Ultra Galaxy Mega Monster Battle. He is also the protagonist of Mega Monster Battle: ULTRA MONSTERS arcade game, which the player assumed.


Mega Monster Battle: Ultra Adventure

Io is a young boy of a ZAP Spacy school with myriad knowledge of monsters. One day while he was in Osaka, Bullton appeared and summoned various monsters to attack the city. During that time, he found the Battle Nizer, which he used to summon Gomora and rescued a Pigmon after being wounded by a Red King. After going through several ordeal with the monster appearances, Io was forcefully dragged into a mysterious planet when Bullton try to retreat to its wormhole.

In said planet, he befriended a wandering Alien Pedan, who would later sacrifice himself to save Io from an Alien Hipporit when the latter try to steal his Battle Nizer. Io would later on adopt the alien's Bemular and join forces with an army of Alien Pedan led by Dorothy to fight their enemy Alien Nackle in exchange for the boy's return to Earth. Alien Nackle was assisted by Yapool, who brings an entire Super Beast Army, as both aliens also created EX Tyrant, which went out of control and eliminated both forces alike. With Io left, he fought against the berserk monster, as well as Yapool's Ace Killer.

He would soon encounter Vittorio, a young Alien Keel Reionics who proclaims himself as Io's rival in the Reionics Battle. The would later fought against an Alien Babarue that manipulated King of Mons and Bajiris under his wing, who would later utilize a baby Arados' power to travel back in the past and stopping Rei from awakening his Rayblood nature. The two succeeded in fighting him and Io himself managed to meet the original Ultraman, who entrusted the future to the young boy's hands before freeing Arados and the party to escape the planet.

In the present day, they faced the Reionics' mastermind Alien Rayblood, who reveals that the battle was simply made to absorb the strongest Reionics' powers and reviving himself, doing so by Silver Bloome's own help. Io's transaction into a Reionics is also part of the plan, made with the help of Pigmon, who is also Rayblood's own follower. Rayblood soon unveils Prometheus, an invasion weapon made by mankind and transform it into Deathfacer as his new body. Before Rayblood can unleash the Neo Maxima Cannon, Pigmon defected to Io at the last minute and Bemular sacrificed itself by shielding the party. Io fought the possessed robot with Gomora and and Vittorio's EX Gomora before finishing him with W Super Oscillatory Wave (Zero Shoot).

Mega Monster Battle: Ultra Adventure NEO

Io reappears and assisted Ai Asama/Red King and recharged Vittorio's energy by sharing his Reionics energy. He also participated in the battle against Rayblood/EX Zetton and won the battle through Seven's help.

Powers and Weapons

  • Battle Nizer: A Reionics himself, Io is in possession of a Battle Nizer, summoning and capturing monsters in his possession. His monsters are
    • Gomora: A monster that's already within the device upon being discovered by Io. Gomora is usually portrayed as an anti-hero and only fights once being summoned by Io to prove his strength.
    • Pigmon: Rayblood's former follower, Pigmon has the ability to detect dangers and other monsters. It ends its sentences with "Piii..".
    • Bemular: Alien Hipporit's former monster, Io adopted it after being defeated by Gomora and its master died at the hands of the Alien Pedan.
    • EX Gomora: Vittorio's monster, it was lent to Io in the final battle against Rayblood-possessed Deathfacer.
  • Energy Sharing: Io exhibited the ability to share his Reionics energies to heal others, doing so to fix Vittorio's damaged Neo Battle Nizer.



  • In ULTRA MONSTERS, players can also face Io himself in the EX Round. Said boy was heard talking to the viewers, though his voice actor remains unknown.
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