Rodan is a major character in the Godzilla series. He appears as the main antagonist in the 1956 film Rodan and a supporting antagonist in the 2004 film Godzilla: Final Wars.
In 1956's Rodan, there were two Rodans, a male and a female, both implied to be mates. They were awakened by mining operations in Kitamatsu along with a swarm of prehistoric insects called Meganulons. One of the creatures hatched from an egg located inside an underground cavern and proceeded to devour several Meganulons before flying out of the cavern. Rodan performed an elusive airborne prowl across various Pacific countries such as China, the Philippines and Ckinawa before finally revealing itself after it emerged from the foot of Mount Aso. As word spread of the monster's existence, no time was wasted, as the Japanese air force pursued the threat, leading directly to the city of Fukuoka. Following a fierce aerial dogfight, a fighter jet crashed into Rodan's wing, injuring the beast and neutralizing its ability to fly at supersonic speeds, although this does not stop Rodan from laying waste to the city. Soon enough, a second Rodan appears to escort the other to safety, ending the rampage. As the two monsters prepare to hibernate by returning to their nest in Mount Aso, Japan's defense force performs a last-ditch effort to defeat the Rodans by bombarding the active volcano, triggering an eruption. As the two monsters attempt to escape, one is incapacitated by the lava and falls, burning to death. The second Rodan flew down to its dying companion, incinerating itself, leaving both Rodans to burn away in the molten rock.
Ghidorah, the Three-Headed Monster
Rodan went on to cross over into the Godzilla series. Whether another Rodan entirely, or a survivor from 1956, this Rodan was resurrected by accumulated volcanic gas under Mount Aso, appearing in Ghidorah, the Three-Headed Monster in 1964 when he broke out of the crust of the volcano and started fighting Godzilla. When Mothra asked Godzilla and Rodan to assist her in fighting King Ghidorah, the humans asked the Shobijin to translate the conservation between the monsters. The Shobijin translated that Rodan argued that it does not matter to him if the human race perishes, to which Godzilla agreed and stated that they have always had trouble with men and men hate them. Mothra gave up convincing the two to help her out, and resolved to fight King Ghidorah alone, much to the humans' dismay, knowing that the larva wouldn't stand a chance. Rodan and Godzilla, suddenly feeling sympathetic for Mothra after watching King Ghidorah attack her, came to help her out as she had requested. Rodan helped get Mothra to ride him and shoot silk at Ghidorah as Godzilla grabbed Ghidorah from behind and held him still so he could become cocooned in the silk. Ghidorah was overwhelmed by the combined force of the three kaiju and flew back to space. Godzilla and Rodan then watched Mothra and the Shobijin swim back to Infant Island. In this film, Rodan is portrayed as being about as tall as Godzilla with a wingspan a little wider than he is tall, while later installments portrayed Rodan as significantly smaller than Godzilla.
Invasion of Astro-Monster
Rodan appeared again with Godzilla in Invasion of Astro-Monster, where they were both transported to Planet X. They battled King Ghidorah before being mind-controlled by the Xiliens and sent to destroy Earth's cities. The two monsters again fought King Ghidorah when the mind control was broken by the A-Cycle Light Ray Gun.
Destroy All Monsters
In Destroy All Monsters, Rodan was again controlled by aliens, the Kilaaks, to attack Moscow. Again the mind control was broken and the monsters fought King Ghidorah. After King Ghidorah was defeated, Rodan was set on fire by a rogue Fire Dragon, but he recovered, and is later shown with the other monsters to be peacefully inhabiting Monsterland. Rodan would only appear again in the Showa series in stock footage used for Godzilla vs. Gigan, Godzilla vs. Megalon, and Terror of MechaGodzilla.
Godzilla vs. Megalon
While Rodan only appears through stock footage, his small role in the film is somewhat significant. Rodan and Anguirus are resting on Monster Island when a Nuclear Bomb is tested nearby, creating a massive fissure and a massive earthquake which crippled both the island and the capital city of Seatopia under the ocean close by. Rodan tries to escape, but Anguirus falls on him and both of the Kaiju fall into the growing chasm. This act of destruction by the humans was the last straw for the Seatopian people, who commanded Megalon to attack the humans for their perceived crimes.
Godzilla vs. MechaGodzilla 2
Rodan returned in Godzilla vs. MechaGodzilla 2, where he sought to protect Baby Godzilla, whose egg was in Rodan's nest. Rodan played a vital role in the film's climax, sacrificing his own life to revive Godzilla by transferring his life-energy to him. In this film, Rodan is noticeably proportionally much smaller compared to Godzilla than in his appearances in the Showa series, standing only about two-thirds as tall as Godzilla and having a wingspan not too much larger than Godzilla's height. The prominent rows of spines on his belly are replaced with overlapping ridges of bone, and he has three spines on his head instead of two (the outer two curve outwards and the center curves up), as well as a wider beak and more predatory face. Heisei Rodan does have some of his predecessor's durability, withstanding several blasts from both Godzilla and Mechagodzilla, and kept his speed and shockwave abilities as well as a stronger pecking attack that can shatter boulders. After being defeated and left for dead by Godzilla following a fight on the small island where his and Baby Godzilla's eggs are found, Rodan was revived by the psychic song of an ancient plant that had covered the eggs. Godzilla's radiation mutated Rodan into Fire Rodan, changing his colors from brown and tan to brick red and light yellow/gold. Fire Rodan also gained a uranium heat ray as a weapon, similar to Godzilla's atomic breath. Besides that, Fire Rodan remained basically the same as Rodan.
Fire Rodan is a more powerful form of Rodan that appeared in Godzilla vs. MechaGodzilla 2. As a children's choir sang to Baby Godzilla, Rodan heard the song miles away on the island where he was killed. He absorbed the nuclear energy from Godzilla and transformed into Fire Rodan, and he took off to save his surrogate brother. He caught the capsule that was carrying the baby, and flew it off towards a city. He was attacked by the Garuda and then by MechaGodzilla, who made him fly into a building. The humans' attention was then turned to the arriving Godzilla, and they battled him. Godzilla was defeated and paralyzed by Super MechaGodzilla, and Fire Rodan acted to save the life of his surrogate brother, and flew on top of Godzilla's body. He gave his life force and melted into Godzilla, healing his damaged second brain and giving him the power of the Spiral Beam. With Fire Rodan's power, Godzilla destroyed Super MechaGodzilla, and took Baby Godzilla out to sea.
On July 26, 2014, Rodan was confirmed to be appearing in Godzilla 2, along with Mothra and King Ghidorah.Holy Mothra: Gareth Edwards Reveals ‘Godzilla 2′ Monsters At Comic-Con