Ultraman Wiki

Boasaurus (ボアザウルス Boazaurusu) is a Kaiju who appeared in Mirrorman, being formed by three 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 named Etusko, 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 easy attacks before being forced to fly away from the scene by SMG in the Jumbo Phoenix. The Jumbo Phoenix let Boasaurus go and focused on the construction site Mirrorman was still holding up, using a crane to help pull up a main girder. The apartment was eventually evacuated with Mirrorman letting the construction thing crash upon it eventually, saving the day.

Generation II

Nearly a month after Boasaurus's first appearance, it was soon reborn 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 while the kidnapped and killed various individuals that were dangerous to their conquest. Before long the Invades threatened SGM not to launch the Jumbo Phoenix under the threat of killing their hostages. Eventually everything went as planned with the Red Bird went about destroying the surrounding area, but Kyotaro and a man named Yuichi managed to save Asako, foiling their plans. The five Invaders that failed to keep them from escaping proceeded to fuse together and form the reborn Boasaurus, known as Boasuaurus II. Kyotaro soon transformed into Mirrorman using broken glass from a mirror and confronted the malicious monster in battle. The hero dodged Boasaurus's explosive mouth mist and soon overpowered him in melee. However, the Red Bird assisted Boasaurus by firing its beam at Mirrorman's back. This allowed the alien monster to fiercely assault the hero. This forced Mirrorman to dodge attacks from both foes although he managed to knock Boasaurus down and use some karate chops on the back of his neck. The fight gained intensity, Boasaurus at once point kangaroo kicking Mirrorman to the ground. The alien monster then ensnared the hero so Red Bird could shock him with a pair of wired electric nodes from its underside. The Jumbo Phoenix soon arrived to attack Red Bird, forcing Boasaurus to fight alone. As the fight continued the hero used the Mirror Knife in Boasaurus's face to stun him. After Boasaurus attempted and failed to charge at Mirrorman, the hero used the Silver Cross that caused him to explode.


  • Boasaurus is a recycled Smoke Ness suit.
  • Versions of Boasaurus 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.
  • Generation I of Boasaurus emits a Zumbolar roar with an echo effect added at the end.


  • Height: 54 m
  • Weight: 31,000 t
  • Origin: Planet X
Powers and Weapons
  • Strength: The first Boasaurus had great strength, being able to throw Mirrorman around with ease.
  • Flight: Boasaurus I can fly at will.
  • 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.



Generation I

Generation II


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