Manda is a kaiju similar to a Chinese dragon that first appeared in the Toho film Astragon.
Manda, a huge sea serpent, is the god and protector of the ancient civilization of Mu. It became an inmate of Monsterland on the Ogasawara islands but was set free by the alien Kilaks to participate with Godzilla, Mothra, and Rodan in an all-out assault on Tokyo in Destroy All Monsters.
He was present as a spectator for the final confrontation against King Ghidorah at the base of Mount Fuji and returned in peace to Monsterland after Godzilla victory over the golden dragon
In the Millennium series, Manda is the first monster to be killed in Godzilla: Final Wars, playing a minor role as an adversary of the Gotengo.
More about mythological dragons.