|Home world:||Katra Meteorite|
|First appearance:||Ultraman Cosmos episode 23: "Luna v.s. Luna"|
Subtitle: Protein Life Form (変幻生命体 Hengen Seimei-tai?)
Ultraman CosmosEditGelworm was a kaiju whom had lived its life on a tiny meteorite with its mate. When the gelworms were separated, The mate was trapped on the meteorite, which was then transferred to a university, where it was being tested with special radiation that was causing her great pain. The male Gelworm tried many times to reunite with its mate on the meteor, taking on the forms of several people to infiltrate the university and steal the meteorite back. Upon taking the form of a scientist, Gelworm nearly managed to complete the task, but was discovered by Keisuke and the shopkeeper and was forced to run away until he ran into a laboratory and accidentally exposed himself to a freezing gas. Once the gas started to somehow electrify the replica, Gelworm turned into his larger form.
Once Gelworm grew larger EYES arrived on the scene only for him to evade their attacks. Once an energy net was dropped everything seemed fine until Gelworm's meteorite reacted, making him react and shake off the net. Musashi turned into Ultraman Cosmos to save the fighter before fighting Gelworm. Gelworm continued trying to make his way towards his meteorite, but Cosmos managed to hold him off until the creature used it's pincers to turn itself into Imitation Cosmos. Imitation Cosmos then fought Ultraman Cosmos. For a full minute neither of them could gain an upper hand on one another until Imitation Cosmos attempted the Cosmos Palm Beam only to realize he could not. Once Cosmos used the Cosmos Palm Beam, Imitation Cosmos reverted back into Gelworm. Once he turned back into his normal form he turned into his smaller form once he was near his meteorite. On returning to it's meteorite it was discovered that he had a mate and would able to live peacefully for the rest of his days.
- Suit actor: Kazunori Yokoo
- Gelworm's roar is a reused Gazort roar.
- Imitation Ultraman Cosmos' suit is reused from the backup Luna Mode suit.
- Imitation Ultraman Cosmos' grunts are low pitched Cosmos Luna Mode grunts.
- Height: 16.5 cm ~ 65 m
- Weight: 8 g ~ 67,000 t
- Origin: Katra meteorite
Powers and WeaponsEdit
- DNA Absorb: Gelworm can absorb the DNA of others by biting them with its pincers.
- Size Change: Gelworm can change from his original tiny size to that of a monster at any moment.
- If Gelworm is exposed to radiation it will cause him great pain.
Imitation Ultraman Cosmos (ニセウルトラマンコスモス Nise Urutoraman Kosumosu?) is the form that Gelworm takes while battling Ultraman Cosmos.
- Height: 47 m
- Weight: 42, 000 t
- Extreme Speed: Like Ultraman Cosmos, Imitation Cosmos can move at blinding speeds.
- Extraordinary Jumper: Imitation Cosmos can jump extremely high into the air.