There is no evidence that the Dragon in the film The 7th Voyage of Sinbad has any name at all, although the name “Magog” is mentioned in reference to it in tthe eponymous Dell comic published in 1958. The name “Taro “ was dubbed by a YOUtube poster , InfernoRoldan, who apparently did not speak English as a first language. This poster heard the command “folllow” issued by Sokurah to the Nameless Dragon as “Taro” , hence the following Nomen Dubium, “Taro”. The Dragon remains nameless in the script for the film. YouTube link responsible for this error :
Taro is a large green lizard-like dragon and one of the minor antagonists from the 1958 film The Seventh Voyage of Sinbad along with Cyclops, Roc and the Living Skeleton. He is one of the most iconic creatures of the film.q
Taro's body was likely designed in likeness to the Tuatara (and bears a resemblance to a previous Harryhausen creation), with his head likened to a traditional Dragon's (horns, ears, etc). The dragon was truly a work of imagination, for such a design for a dragon was never quite shown in previous films. Taro was huge in size, being even larger than the Cyclops.
The Dragon acted as a personal guard dog use by the evil magician Sokura. Like a guard dog, the dragon was very obedient and protective, and would do whatever it could to protect, or do what it thought was protecting, which included fighting a cyclops. It wouldn't stop fighting the cyclops, and continued to fight the other beast, until it killed the cyclops in a bite to the neck. The dragon was also capable of shooting out large flames from its mouth and used sharp teeth as effective weapons in combat.
Protecting Sokura’s hidden castle, Taro watched the entrance as if a loyal guard dog. Preventing Cyclopes from entering his master’s domain, the fire-breathing dragon was soon set free as Sinbad and Princess Parisa fled from the sorcerer’s fortress. In order to escape the wrath of the last of the Cyclops, Sinbad unleashed the reptile to do combat with the brute. Attacking the horned, one-eyed monster with fangs and claws, Taro forced the creature back and crushed its throat with his jaws. While Sinbad and the princess escaped, Sokura emerged from the entrance, instructing his loyal dragon to follow!
Waiting on the shoreline, a gigantic crossbow had been constructed to deal with the deadly denizens of the Colossa. The arrow was launched, striking the dragon in the chest and sending it crashing to the beach, directly on top of Sokura! The magician was killed and as the mortals returned to Sinbad’s ship, the dragon’s movements slowed to a stop as he died too.