In its first appearance in Son of Godzilla, Kumonga was a giant spider native to Solgell Island which slept in a valley on the island. Awakened by a stray boulder kicked into his valley by Minilla, Kumonga began threatening a team of humans stranded on the island and eventually captured both Minilla and Kamacuras. Kumonga was killed by the combined might of Minilla and Godzilla, but a second Kumonga appeared in Destroy All Monsters, where it was one of the monsters contained on Monsterland at the end of the 20th century. Kumonga assisted Godzilla and the monsters of Earth in battle against King Ghidorah, trapping King Ghidorah under webbing alongside Mothra. Kumonga reappeared in the final film of the Millennium series, Godzilla: Final Wars, where it was under the control of the Xiliens and unleashed in Arizona. Kumonga battled Godzilla in New Guinea under the invaders' commands, but was defeated.
Kumonga's name comes from kumo (クモ), which is the Japanese word for "spider." The Kumonga featured in Destroy All Monsters is sometimes referred to in books as Second Generation Kumonga (二代目クモンガ Nidaime Kumonga), while the Kumonga from Godzilla: Final Wars is called Kumonga (3rd Generation) (クモンガ（３代目） Kumonga Sandaime).
Kumonga's name in the English dubs of Son of Godzilla and Destroy All Monsters is Spiga or Spiega, which comes from "spider."
Kumonga is a gigantic spider, with a mostly black body covered in gold stripes. Kumonga's body has some tufts of black hair on it, most prominently on its legs. Kumonga's head possesses six eyes, which are either purple or blue in color, and chelicerae and fangs around its mouth. In the Showa series, Kumonga's mouth is filled with urticating bristles and can project a venomous stinger, while these features are not present in the Millennium incarnation. Kumonga has eight legs, each with three articulated joints. In Godzilla: Final Wars, Kumonga has brighter and more numerous gold stripes on its body, and its body is more angled toward the ground.
In Son of Godzilla, Kumonga is a vicious predator that attacks anything it sees. Kumonga is not averse to attacking humans, as it spends a good deal of time trying to capture Saeko and Goro and later attacking them and the team of scientists in a cave. The Kumonga in Destroy All Monsters is shown to live peacefully with the other monsters on Monsterland, and assists them in the final battle against King Ghidorah.
In the main Godzilla comics published by IDW Publishing, Kumonga appears to simply be a rampaging monster at first, but by the final arc of Godzilla: Ongoing becomes a loyal ally to the other Earth monsters and Kiryu against the invading space monsters. Kumonga even hitches a ride on Kiryu's back from Monster Island to New York to help Mothra battle Monster X. In Godzilla: Rulers of Earth, Kumonga takes part in the final battle in Los Angeles against the Trilopods alongside the other Earth monsters.
According to the research of Dr. Matsumiya, Kumonga is a gigantic spider native to Solgell Island, which while not active and hunting hibernates for years at a time under a valley. It is unknown if Kumonga was affected at all by the radiation storms on the island that mutated the native giant praying mantises into Kamacuras, or if it was simply always 45 meters tall.
Son of Godzilla
While protecting Saeko Matsumiya from a Kamacuras, Minilla accidentally knocked a boulder into Kumonga's valley, awakening the giant spider from its sleep. Kumonga attacked Saeko and Goro Maki when they tried to reach Saeko's cave, but they escaped. Kumonga followed them to the cave and tried to break in, trapping them and the scientists there. Eventually Kumonga left and trapped the Kamacuras and Minilla in its web. Kumonga killed the Kamacuras with its venom, but Godzilla arrived before it could do the same to Minilla. Kumonga and Godzilla battled, with Kumonga damaging Godzilla's eye and trapping him in webbing. Minilla came to his father's aid, and eventually Godzilla and his son were able to defeat Kumonga by blasting it at the same time with their atomic breath, setting the giant spider ablaze.
Destroy All Monsters
By the end of the 20th century, a second Kumonga was living on Monsterland alongside the other monsters of Earth. One day, the Kilaaks attacked the island and took control of the monsters, sending them to attack various cities across the world. After the humans severed the Kilaaks' control over the monsters, Kumonga and the other monsters prepared to assault the aliens' base under Mount Fuji. The Kilaaks responded by sending King Ghidorah to attack the Earth monsters. Kumonga and Mothra assisted in the battle by encasing King Ghidorah in webbing. Kumonga was then returned to the island along with the other monsters to live in peace.
Godzilla: Final Wars
In 20XX, Kumonga appeared in Arizona and destroyed a trailer park before being suddenly teleported away along with all of the other monsters rampaging across Earth by the Xiliens, who claimed to want to save Earth. However, the Xiliens' true motives were revealed, and the Controller of Planet X unleashed all of the monsters to resume their destruction of the planet's major cities. In response, the Earth Defense Force freed Godzillafrom Area G and had him defeat the Xiliens' monsters. The Controller unleashed Kumonga in New Guinea to battle Godzilla. Kumonga was able to use its jumping ability to avoid Godzilla's attacks while trapping him in webbing, but Godzilla grabbed one of Kumonga's web strands and swung it through the air before letting go, sending Kumonga soaring over the horizon.
Kumonga can shoot a thick webbing and a stinger from his mandibles. Kumonga has prehensile pedipalps that can be used to grab small prey. The Showa version was able to survive multiple hits from Godzilla's atomic ray. The Millennium Kumonga's web was able to expand on contact with air from a single thread into a net for incapacitating foes. It also has long legs ending in sharp points which can be used to skewer opponents or crush through materials like in a scene in the movie Godzilla: Final Wars. It also appears to have jumping abilities. The Showa version also had a venomous stinger that instantly killed Kamacuras. In Godzilla: Rulers of Earth, Kumonga appeared to regenerate a severed leg it had suffered in a battle with Gigan.
- Unlike most real spiders, Kumonga does not have spinnerets, firing silk from its mouth instead. This ability may have been inspired by the spitting spider.
- Kumonga is the only Xilien-controlled monster in Godzilla: Final Wars who they never deploy to a heavily populated area.