Titanosaurus is an aquatic dinosaur monster and the secondary antagonist in Terror of Mechagodzilla.
Titanosaurus was an enormous ocean dwelling dinosaur that lived in seclusion in the Pacific Ocean, until it was taken control of by the mad scientist, Shinji Mafune. After he became obsessed with studying the brain waves of marine life, Mafune lost his academic credentials and was cast out of the scientific community and shunned by his fellow biologists. With help from the aliens of Black Hole Planet 3, Mafune took control of Titanosaurus after it had attacked a submarine that was investigating the remains of the original Mechagodzilla, transforming the normally peaceful dinosaur into a vicious monster. Mafune then reconstructed Mechagodzilla, while Titanosaurus began attacking Tokyo. Godzilla went to engage the aquatic dinosaur, but it proved to be a highly challenging opponent. Things only got worse when Mechagodzilla arrived and joined forces with Titanosaurus. The INTERPOL Agency realized that Titanosaurus had a weakness, supersonic waves. After Katsura, Mafune's daughter who was in control of Mechagodzilla, allowed herself to die, the robotic titan was left without control. Godzilla twisted its head off and eventually destroyed it with a blast of atomic fire. Titanosaurus was blasted with several supersonic waves and eventually defeated by blasts of atomic fire from Godzilla.
Titanosaurus appears in the videogame Godzilla: Unleashed as a playable monster,exclusive to the Wii version of the game, who has sided with the Mutants faction.
His entry in the Character Bios states:
"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."
Titanosaurus possesses enormous strength (enough to lift Godzilla himself into the air using only his mouth) thanks to its huge size and it can use the fin on its tail to generate huge gusts of wind and whirlpools in the water. Titanosaurus is also amphibious and in Godzilla: Unleashed, it can emit powerful sonic beams. This may explain the reason sonic waves are his weakness, since they can disrupt the ones he uses.
- The Titanosaurus was an actual species of dinosaur, but had little in common with the monster, being a land-dwelling sauropod.
- Originally, Titanosaurus was going to be formed from two monsters called Titans combining, but the budget only allowed for one costume to be made.
- In Godzilla: Final Wars, Titanosaurus made a cameo appearance and as a toy and a flashback.
- Titanosaurus's design was unique for kaijus of the time, being a throwback to the dinosaur based monsters from the 60's. Most monsters of the time were space monsters with bizarre designs.