on the receiving end of Jack's Specium Ray. : Another monster from the Mesozoic era and Gudon's prey. Its name is due to the inverted body position, and is armed with a pair of anesthesia-laced tails as its weapons. Its egg was discovered at the Shinjuku construction site where everyone except Go and Jirō dismissed it as a rock. The egg traveled underground and injured Aki and the other four victims within a toppled shopping mall. The egg hatched to reveal Twin Tail and managed to defeat Jack when its predator Gudon join the battle before luring the latter monster away from the city. At some point later on, the resurfaced Twin Tail was blinded by MAT's bazookas thanks to Jack's assistance and was killed from Gudon's bite. : A carnivorous nocturnal monster that lives on the and is able to spit . Like a chameleon, Gorbagos can either turn invisible or changing its skin color to blend in with the surrounding. The monster was first sighted by Jirō through his monochrome camera, but was dismissed by many as a photomanipulation on the young boy's part except Go and Ken. After Go spotted the monster attacking a group of campers at night, the MAT members used rainbow-colored paints to mark Gorbagos. Now stripped of its camouflage ability, Gorbagos was forced to hide underground and ambush the MAT members on the next day. After his MAT Arrow was taken down, Go transform into Jack and fired his Specium Ray on the monster's neck. : The gold-skinned younger brother of Arstron and exhales . The monster's field of vision is limited to 20 meters but it compensate this for an enhanced sense of hearing and eats golds. First spotted in Osugi Valley, Go was sent to destroy the monster with Kishida's X Bomb but Ghostron's sudden response to his presence caused the missile to be lodged into its tail with the time limit of 10 hours. Despite its initial movement to Tokyo, Ghostron changed course to the Hibi Kagaku dynamite factory due to its attraction to the loud siren noise. MAT's attempt to sedate Ghostron failed but Go managed to lure the monster away to a safe zone and transformed into Jack to bring it to space for safe detonation. : A lion-themed monster that was sleeping in Minamidaitōjima. It has a durable skin, energy storing mane, a claw on each hands