Kaiteigagan (カイテイガガン Kaiteigagan) was a Terrible-Monster that appeared in episode 34 of the TV series, Ultraman Ace.
Subtitle: Rainbow Terrible-Monster (虹超獣 Niji Chōjū)
Kaiteigagan was a Terrible-Monster composed of sea shells created to destroy boats off the coast. Kaiteigagan first appeared in the middle of the ocean were it was attacked by TAC's fighter jets. Wile not being able to kill it, they did manage to drive it back to under the waves. Kaiteigagan, later, reappeared in the coast of a beach. TAC once again attacked it with fighter jets. However this time, Kaiteigagan fled to land! Seiji Hokuto quickly transformed into Ultraman Ace to do battle with the Terrible-Monster. While Kaiteigagan tried its hardest and used all the super powers at its disposal, it was no match for the hero and was beat into submission. After a massive beatdown, Ace killed the Terrible-Monster with his Metalium Beam, blowing it up.
- Kaiteigagan's roar is a slowed down King Maimai roar.
- In the Monster Encyclopedia series, Kaiteigagan uses a reversed Birdon roar.
- Kaiteigagan is one of the monsters that make up Belyudra's right arm in Mega Monster Battle: Ultra Galaxy Legends The Movie.
- Height: 45 m
- Weight: 37,000 t
- Powers and Weapons
- Adept Swimmer: Being an aquatic monster, Kaiteigagan can swim at moderate speeds.
- Gas: Kaiteigagan can emit a gas from his mouth.
- Stun Ray: Kaiteigagan can release a purple ray from his mouth that can stun enemies.
- Missiles: Kaiteigagan can fire missiles from its mouth in rapid succession.
|Ultraman Ace Kaiju|
|Verokron | Yapool | Chameleking | Vakishim | Garan | Aribunta | Giron Man | Brocken | Alien Metron Jr. | Doragory | Muruchi II | Gammas | Zaigon | Alien Antira | Unitang | Sabotendar | Baraba | Ace Killer | Ace Robot | King Crab | Cattle God | Cowra | She-Devil | Hotarunga | Black Pigeon | Android Couple | King Kappa | Zemistlar | Aprasar | Aprasar Fairy | Space Mask | Black Satan | Giant Yapool | Mazaron Man | Yojo | Mazarius | Alien Orion | Sphinx | Alien Hipporit | Lunaticks | Undergroundmon | Gitagitanga | Red Jack | Baktari | Coakes | Bad Baalon | Kaiteigagan | Dreamgillas | Soundgillar | Machless | Snowgiran | Namahage | Alien Fire | Firemons | Alien Steal | Kaimanda | Shishigoran | Iceron | Woo II | Fubugirara | Onidevil | Gasgegon | Daidarahoshi | Hanzagiran | Verokron II | Yapool Woman | Univerlages | Aquarius | Alien Revole | Signalion | Geegon | Alien Simon | Jumbo King|