Titanosaurus shares his name with a real dinosaur species, though they do not share many similarities other than that.
Titanosaurus is a deep-sea dwelling creature who sports a fin on his tail and along his back. He also has a rather a long neck.
Titanosaurus is technically not evil since he was mind-controlled in Terror of MechaGodzilla. Some of the characters in the film also mention that Titanosaurus has a calm nature and would normally not attack.
An amphibious dinosaur found in the Pacific Ocean, the character appeared only once, as one of two antagonists in the film.
In Terror of MechaGodzilla, a mad scientist named Shinji Mafune becomes so obsessed with studying the brain patterns of marine life that he loses his academic credentials and is cast out from the scientific community. Quickly, descending into madness, Mafune is able to gain mental control of Titanosaurus, with the help of aliens from Black Hole Planet 3, after he attacks a submarine investigating the remains of the destroyed MechaGodzilla, from the previous film, Godzilla vs. MechaGodzilla. The normally peaceful Titanosaurus becomes a frightening, intense monster, and when Dr. Mafune rebuilds MechaGodzilla, both monsters combine their forces, to begin Mafune's revenge on humanity. Both are ultimately defeated by Godzilla.
At first, Godzilla arrived at Tokyo to save the people and help the military, thinking that he can take down Titanosaurus more easily without the robot MechaGodzilla. However, Titanosaurus was even more powerful than anyone could have imagined without superpowers. The INTERPOL Agency figured out if Titanosaurus is exposed to supersonic waves, then Godzilla will have more energy to defeat MechaGodzilla. After Katsura committed suicide, MechaGodzilla was no longer controlled since Godzilla pulled off his head, making him blind. Godzilla immediately destroyed MechaGodzilla by aiming his atomic breath at the robot's body and defeated Titanosaurus with two shots of atomic breath after the dinosaur was shot by several waves on his body's attached device, the Supersonic Wave Oscillator. The world was saved by Godzilla for the eighth time.
Titanosaurus can whip up a cyclone with his tail by opening the fin from the tip of his tail and swinging it's tail back and forth.
Titanosaurus was cut from Godzilla: Save the Earth. This was due to licensing errors, so Megaguirus took Titanosaurus' place. He can still be seen in the concept art though, wading in the water of an icy level. Titanosaurus appears as a playable character in Godzilla: Unleashed.
"Titanosaurus is a prehistoric throwback-a primitive monster from an ancient age who has managed somehow to persist in contemporary times. Titanosaurus lives deep in the ocean, hibernating for hundreds of years in a stretch. In recent years, humans have disturbed Titanosaurus, increasingly incurring his wrath. Though not specifically evil, Titanosaurus holds no allegiance to any particular ideology, and would not hesitate to secure additional power for himself should the opportunity arise. This frequently places himself in opposition to Earth Defenders and the Global Defense Force. Titanosaurus employs his towering height, powerful tail, and sonic waves to intimidate or subjugate any beings who dare to disrupt his ancient lifecycle."
In the original script of Terror of MechaGodzilla, Titanosaurus was supposed to be actually two different monsters who would later combine into Titanosaurus, known as the Titans; but because of budget problems, Toho was only able to make the Titanosaurus suit and not the two other monsters.
The name "Titanosaurus" was also given to a sauropod dinosaur. In real life, the Titanosaurus was a four-legged herbivore and was not an aquatic creature.
With his colorful, dinosaurian design and (though weakly defined) personality, Titanosaurus is unique for a 1970's monster, most of which were space monsters with strange, unnatural and illogical body designs, and is an obvious throw-back to the more successful dinosaur monsters of the 1960's like Baragon and Gorosaurus.
Titanosaurus' fate is not known. After being weakened by Interpol's supersonic transmitter, the creature is hit directly in the chest by Godzilla's atomic ray, and falls backwards off of the cliff into the sea. It is unknown if Titanosaurus died in the battle, or recovered and swam away. Some believe that, since Titanosaurus was not among the monsters living in Monsterland in 1999, the creature did indeed perish. However, as the film Destroy All Monsters, which features Monsterland and takes place in 1999, was produced in 1968, seven years before Terror of MechaGodzilla was produced, this theory holds little water. After all, other monsters from films made before Destroy All Monsters, such as King Kong, the Giant Octopus and Ebirah are not seen living in Monsterland, either.
In Godzilla: Final Wars, a boy is seen playing with Godzilla monster figures, including a toy figure of Titanosaurus.
In Godzilla: Unleashed, Titanosaurus only joins the mutants to stop the G.D.F. from attacking him. Some fans said that Titanosaurus should be an Earth defender in Godzilla: Unleashed instead of a mutant. This is because in the movie, he was being controlled, so he is not evil in the first place. Furthermore, Titanosaurus has a sonic beam, which is ironic, considering that sonic energy is what lead to the downfall of his movie counterpart.
Titanosaurus is one of the few monsters to actually be taken down by humans.