Boasaurus (ボアザウルス Boazaurusu) is a Kaiju who appeared in Mirrorman, being formed by multiple Invaders fusing together. The first was summoned to destroy a crashed Invader ship while the second was to protect the Red Bird ship during its mission on Earth from Mirrorman.

Subtitle: Giant Space Monster (巨大宇宙怪獣 Kyodai Uchū Kaijū)



Generation I

On one normal afternoon in a city, a spaceship suddenly came from the sky and crashed into an apartment building. People panicked fleeing from the scene while others watched in terror as injured people were pulled out, unable to respond to anything. Eventually the SMG came to investigate the site, identifying the ship as belonging to the Invaders and quickly got to work with saving people from in the apartments. Unknown to them, three Invaders in human disguise had come to the area, intending to destroy their lost vessel to keep humans from obtaining their technology. While several SMG members entered the apartment to save a missing girl, the trio fused together to form the mighty beast known as Boasuarus.

The monster immediately went about its mission to destroy the saucer and apartments. Mirrorman quickly appeared and fought against the monster, Boasaurus proving to be a difficult opponent in combat. Several times throughout the fight, Mirrorman was thrown about by the monster from its great strength, eventually into a building being constructed near the apartment. This caused the construction site to begin to fall down upon the other building. Mirrorman quickly held it up trying to keep it from falling. Boasaurus took advantage of this, getting in several freebie attacks before being forced to fly away from the scene by SMG. The team attempted to chase after the monster, however they eventually found it to have disappeared. Unsure of its whereabouts, the SMG decided to get back to the apartments seeing it as more important. The apartment was later emptied of people with Mirrorman letting the construction thing crash upon it eventually, saving the day.

Generation II

Nearly a month after the first Boasaurus's appearance, a stronger second was soon to be born as part of yet another vile plot by the Invaders. From Planet X, the Invaders sent a powerful warship known as the Red Bird to conquer Earth, sending five other minions before its arrival to make sure nothing went wrong. The five Invaders captured Mirrorman and locked him in a warehouse, intending to leave him to die there so he could no longer interfere with their conquest. Eventually everything went as planned with the Red Bird finally arriving on Earth in the vicinity of Mirrorman's imprisonment and went about destroying the surrounding area. The SMG attempted to stop it only for the five Invaders to fuse together and created a new Boasaurus, known as Boasuaurus II. While the Invaders had seemingly won, it was not true as Mirrorman managed to escape his captive status. He transformed and confronted the malicious fiends in a battle. The fight was furious, Mirrorman came to be in peril like his previous battle with the first Boasaurus, the successor and the Red Bird ship ganged up on the valiant hero with the beast holding him in place as the warship attacked him with its deadly beams. All seemed lost until the SMG came into to assist Mirrorman by destroying the Red Bird, allowing Mirrorman to kick back Boasaurus II and finally finish off the monster his ray. After being hit, Boasaurus II fell to the ground lifeless and exploded, killing the Invader born abomination.

  • The first Boasaurus is one of the only monsters never to be defeated by Mirrorman as it escaped before he could do so.
  • Both Boasauruses were formed for a mission involving Invader ships.
  • To tell the difference between generation I and II of Boasaurus, the first one had a beak like tooth in the middle of it's upper lip.


  • Height: 54 m
  • Weight: 31,000 t
  • Origin: TBA
Powers and Weapons

Gen I

  • Strength: The first Boasaurus had great strength, being able to throw Mirrorman around with ease.
  • Flight: Boasaurus I can fly at will.

Gen II

  • Explosive Gas: Boasaurus II can spew forth an explosive mist of various gases, causing buildings to explode.
  • Agility: Boasaurus II is surprisingly agile, jumping around in the air while flipping and dodging Mirrorman's attacks speedily.
  • Kangaroo Kick: Only shown once, Boasaurus II was able to jump back on its tail and springing forward in a double kick similar to what Kangaroos do.



Gen I

Gen II

Mirrorman Kaiju
Iron | Kitty Fire | Darkron | Multi | Noppera-bō | Inbera | Kitty Fire II | Gold Satan | Iron II | Multi II | Invaders | Gravity Machine | Zailas | Shinjuku Rose | Gold Satan II | Noah | King Zaiger | Iron III | Kitty Fire III | Zailas II | Jabala | Kinder | Chamelegon | Aroza | Big Eye | Sphenodon | Darkron II | Taigan | King Wonder | Androsaurus | Coldon | Haebun | Gokibura | Mothgojira | Dustpan | Snake King | Harigojira | Killergon | Gorgosaurus | Mayasaurus | Arigeida | Killersaurus | Pair-Mons King | Mogura King | Smoke Ness | Pair-Mons King β | Gorgosaurus β | Mayasaurus β | Halley Jack | Androsaurus II | Androsaurus Jr. | Magumagon | Zangani | Shadow Mons | Teroringa | Invesaurus | Ghost | Boasaurus | Black Gon | Red Mons | Giranda | Borezaurus II | Iezu | Eletrikzaurus | Dead King
Mirror Fight Kaiju
Mirror Fight Iron | Kitty Fire | Darkron | Noah | Aroza | Zailas | Multi | Inbera | Kitty Fire II | Gold Satan | Iron II | Multi II | Gravity Machine | The Invaders | Gold Satan II | Korudon | King Zaiger | Jabala | Kinder | Chamelegon | Sphenodon | Darkron II | Taigan | Ozma | Big Eye | King Wonder | Androsaurus | Dustpan | Snake King | Harigojira | Killergon | Arigeida | Sea Killersaurus | Pair-Mons King | Gorgosaurus β | MoleKing | Invesaurus | Shadow Mons | Eletrikzaurus | Dead King | Boasaurus | Teroringa
Mirror Fight 2012 Alien Reguran | Iaron | Dorigorus | Dorako | Aroza
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