Jet Jaguar (ジェットジャガー Jetto Jagā) is a fictional character who appears in the Godzilla film Godzilla vs. Megalon (1973).

History
Created from the brilliant mind of Goro Ibuki, Jet Jaguar represented the advancement of technology to its utmost. Working in secret in his lab, the inventor's triumphs didn't go unnoticed. Watching from a distance, agents of Seatopia awaited for their chance to capture the scientist and take hold of the marvelous robot. Lying in shrouding mystery, they awaited to spring their trap at last. Seizing hold of the man and a small boy, they sought to bring him to the undersea kingdom, until the rising Megalon revealed its ghastly face. Unknowingly setting free the humans, the insect raged into its set path, dumbly following the Seatopia controlled Jet Jaguar. Only by using his medallion with its built in override voice command, was Goro able to overthrow Seatopia's control. Witnessing the threat at hand, the inventor immediately ordered the humanoid robot to retrieve Godzilla from the devastated Monster Island. Flying at an unimaginable speed of over mach three, the machine accomplished its mission as it flew ahead of the nuclear saurian that it had summoned.

Instead of obeying the voice override once it returned, though, the metallic warrior dipped into the recesses of its programming and began to operate on its own accord. Seeing the danger that Megalon possessed to life, the machine grew to match the insect's own daunting stature and proceeded to face the creature. Matching and overcoming each tactical move of the Seatopian god, it seemed that the giant would win the day, until another entered the fray. Swooping down from the lisping clouds, the cyborg Gigan stole the victory. Adding its tremendous power to Megalon's, the creatures overtook the robot in a matter of minutes. It wasn't until the summoned Godzilla's arrived did Earth breath a sigh of relief. Fighting back against the duo, Jet Jaguar and Godzilla pushed back the two demons into retreat. Following in an impressive show of intelligence, Godzilla and Jet Jaguar shook hands, the machine showing his gratitude. Watching the dorsal finned behemoth leave, the humanoid robot shrank back down to size, and once again reverted to being controlled through its voice control system. The survival program now lay dormant that Earth is safe.

Origins
Jet Jaguar was the result of a contest Toho had in mid-to-late 1972 for fans to come up with a new hero for them to use (to capitalize on the many tokusatsu and anime superhero and super robot shows that were all the rage at the time). The winner of the contest submitted the drawing of a robot called Red Alone. The robot resembled Ultraman, Spectreman, and Mazinger Z (all of which were very popular at the time). The robot was renamed Jet Jaguar and was set to star in a film vehicle for him, titled Jet Jaguar vs. Megalon, which pitted him against Megalon (a previously unused Godzilla villain). However, Toho figured Jet Jaguar would not be able to carry the film on his own, in screen appearance or marketing value, so during pre-production, even after doing some tests and storyboards, the project was shut down for several weeks, until screenwriter Shinichi Sekizawa was called in to rewrite the script to add Godzilla and Gigan to have more marquee value. The resulting film, Godzilla vs. Megalon, paired Godzilla with Jet Jaguar against both Megalon and Gigan.

Film Appearances
Godzilla vs. Megalon

Other appearances
Jet Jaguar appears in the video games Godzilla Trading Battle (1998), Godzilla: Save the Earth (2004), Godzilla: Unleashed (2007), and Godzilla Unleashed: Double Smash (2007).

Ebirah (エビラ Ebira), is a fictional kaiju (Japanese giant monster) that first appeared in the Showa Godzilla film Godzilla vs. the Sea Monster. He is one of the two main antagonists of the film. So far Ebirah has also appeared in All Monsters Attack and Godzilla: Final Wars.

Origin
Showa series
In Godzilla vs. the Sea Monster, a terrorist organization called the Red Bamboo had set up a base of operations on Letchi Island. The giant shrimp Ebirah was successfully used to destroy any ship that came too close to the island. The Red Bamboo ships used a special extract from the island’s fruit to protect themselves from Ebirah. When a small group of people stranded on the island saw the mutant dinosaur Godzilla sleeping in a cave, they woke him so he could fight Ebirah. Godzilla easily won and injured the crustacean with his atomic ray. The day after, a Red Bamboo ship appeared, but they unknowingly used a placebo and not the fruit extract. Ebirah attacked and tore the ship apart. Godzilla reappeared, but this time, Godzilla pulled off Ebirah’s claws. The wounded Ebirah then fled.
Ebirah was not seen again until he appeared on Monster Island in Ichiro’s dreams in All Monsters Attack. His appearance in this film is simply stock footage utilized from Godzilla vs. the Sea Monster. Ebirah was originally going to appear in Destroy All Monsters, but did not make it to the final draft.

Millennium series
In the Millennium era, Ebirah makes an appearance in Godzilla: Final Wars as one of the many controlled monsters of the Xiliens, a race of extraterrestrial beings. He destroys a factory near Tokyo, and the military forces are sent to destroy him, but are outmatched by the immense crustacean. Instead, the mutant soldiers are called to stop the kaiju. The mutants successfully defeat Ebirah and are about to kill him, when he disappears in a flash of light. The Xiliens arrive and say that they destroyed the monsters to save Earth. However, it is soon found out that the monsters were in fact controlled by the Xiliens all along.
The Gotengo then frees Godzilla from the Antarctic so he could fight the controlled kaiju. The plan is a success and Godzilla successfully defeats all of the kaiju. When he arrives in Tokyo Bay, he faces Ebirah and the smog monster Hedorah. However, they are no match for Godzilla, who blasts them out of the water with his atomic ray and the duo crash into a building, where Ebirah's claw stabs Hedorah's eye. Godzilla fires another blast and knocks out both Ebirah and Hedorah.

Video game appearances
Ebirah has been featured in as a non-playable enemy kaiju in three video games:
Godzilla, King of the Monsters
Godzilla: Save the Earth
Godzilla Unleashed: Double Smash
Ebirah was only featured as a playable character in the Japan-only game Godzilla Trading Battle.

Appearances in comic book
Ebirah made an appearance in the IDW comic book series Godzilla: The Half-Century War.

Biology
Large and bulky, Knifehead is a heavily built Kaiju. Its most notable feature is the long and broad sharp-ended nose, that could easily cut through the armor of a Jaeger. It has a large shell-like armor on its back, while the rest of its body is similar to a goblin shark in appearance.
Knifehead's two large dominant arms and two smaller secondary arms protrude from its belly.  Its large arms each have three clawed digits, the middle digit being significantly larger. Bright yellow lines run through a pattern across its body, with the rest of its body being a dark grey. Its eyes and the interior of its mouth, however, glow blue.

Like Slattern and Scunner, Knifehead's primary arms are actually two fused arms themselves ending in three-digited claws.

History
Knifehead is the largest Category III Kaiju recorded so far, deployed to attack Anchorage, Alaska. On its way to its target, Knifehead moves to attack a fishing boat, but is intercepted by Gipsy Danger. The Jaeger manages to grab and toss the boat out the line of combat. Knifehead attacks Gipsy, but only succeeds in biting at its arm, before being given a severe beating. It takes three shots from Gipsy's Plasmacaster which sent it hurling back into the ocean.
Gipsy Danger's pilots, Yancy and Raleigh Becket, assume Knifehead is dead and let their guard down. Knifehead ambushes them, attacking them from under the sea and tries to bite the Conn-Pod. Raleigh tries to charge Gipsy's left Plasmacaster, but Knifehead grabs Gipsy's arm so he is unable get a shot at it. Knifehead rams the sharp end of its head into Gipsy's left shoulder. It severs the Jaeger's arm and proceeds to rip and tear at Gipsy's severed shoulder using its teeth.

Knifehead tears open the Conn-Pod, and rips Yancy out of the cockpit, hurling him to his death, leaving his brother Raleigh to pilot what remained of Gipsy solo. Knifehead strikes Gipsy with its head and impales Gipsy's left breastplate while it continued to bite at its severed shoulder. However, in its frenzy, it stopped gripping Gipsy's right arm. Raleigh charges the plasma caster and unloads a clip into Knifehead's face, killing it.

Notes
Scunner and Knifehead use the same basic CG body as Trespasser in Pacific Rim.
In a preview of Pacific Rim: Tales From Year Zero, Knifehead's skull can be clearly seen mounted on the room, and in the next page Gipsy Danger's damaged body.
Several identical copies of Knifehead can be seen in the Precursors processing facility (hundreds in concept art of the film). This hints at the idea that there were to be many attacks from this Kaiju type.
Knifehead appears in Pacific Rim: The Video Game.
Knifehead bears a resemblance to Guiron, a similar monster from the Kadokawa Daiei Gamera series.

Gabara (ガバラ, Gabara) is a fictional monster featured in the 1969 Japanese tokusatsu film All Monsters Attack, the tenth Godzilla film to be produced by Toho, which would later be brought to the US under the title Godzilla's Revenge. Gabara is the primary antagonist of the film.

History
All Monsters Attack
Just as All Monsters Attack is one of the more distinctive entries in the Godzilla canon, Gabara is very unique amongst the other Toho-made monsters. It seems that Gabara exists entirely inside the dreams of lead child character Ichiro.
In the context of the film, Gabara is a resident of Ichiro's imaginary Monster Island, and a constant tormentor to the much smaller Minilla, inspired by Ichiro's own real life problems with bullies around his neighborhood. After receiving combat training from his father Godzilla, and extra assistance from the human protagonist, Minilla does successfully challenge the bully. Finally, Gabara was confronted by Godzilla himself, given a sound thrashing, and sent to lick his wounds deep in the jungles of Monster Island.
Despite the film's overuse of stock footage, Gabara was the only original monsters created for the film, along with newly filmed fight scenes and effects.

Go! Greenman
The character did not make any further appearances in the Godzilla film franchise, but did make a 'guest spot' in the fourteenth episode of the short Kyodai (giant superhero) television series Ike! Greenman (Go! Greenman). However, despite this, it's unclear if this means Gabara exists outside of Ichiro's dreams, that Greenman's adventures (or at least that episode) take place within them, or if the two are totally unrelated. The best way to view this situation is similar to Godzilla's appearances on Zone Fighter...only more obscure.

Appearance
The audio commentary for Classic Media's 2008 DVD release of All Monsters Attack humorously compares Gabara to a bipedal cat with car engine problems. Although not based on any real animal (living or extinct), Gabara is very similar to (and more then likely based on) the Oni of Japanese mythology and folklore. His costume design is very reminiscent of these demonic ogre / troll-like beings, further mixing the turquoise scales of a reptile with orange, cat-like fur. He also has three horns on his head, again much like the Oni, whose horns varied between one-to-three on average.
Gabara's ability to electrocute things on contact is possibly a reference to Oni lore, as they too were sometimes associated with the natural forces of lighting and thunder.
Its roar sounds like mocking laughter.

Abilities
Electric bolts generated from its arms and 'Power Horn', of which Gabara can then electrify anything or anyone it touches.

Trivia
Within the context of the film, Gabara is a representation within the dreams of Ichiro, the main character, of a schoolyard bully of the same name. Similarly, Ichiro is represented by Minilla, Godzilla's son. After Godzilla defends his offspring in Ichiro's dreams, Ichiro is able to overcome his fears and confront the real Gabara.
Gabara is the only monster in the Toho universe that exists only in a dream; that is to say, it does not exist in the real world like Toho's other kaiju.
Gabara is the second monster to be defeated by both Godzilla and Minilla. The first was Kumonga.
Gabara is probably an imaginative take on the Oni, an ogre-like race in Japanese mythology. Confirmed Kaiju that are Oni can often be seen in the ongoing Ultraman franchise, with characters like Oni-On, from episode 27 of Ultraman Leo, and Sukunaoni from episode 16 of Ultraman Tiga. Oni are major mainstays in Japanese culture, and are often depicted in fantasy films and TV series beyond the Kaiju Eiga genre, including American produced projects like the 2006 animated movie Hellboy: Sword of Storms.
In a 1990's Monstervision commercial for Turner Network Television (TNT), which used Godzilla film footage with Blue Oyster Cult's related song in a music video like fashion, Gabara is incorrectly referred to as 'Baragon'.
In the Simpsons episode "30 minutes over Tokyo", in the end Gamera, Rodan, Mothra and Godzilla are attacking the Simpsons and Gabara's Laugh like roar is heard.