Gorosaurus is a gigantic prehistoric dinosaur resembling a Allosaurus. He is one of the less popular kaiju and hasn't appeared in any movie since Godzilla vs. Gigan, though he was considered for Godzilla: Final Wars.
Gorosaurus first appeared in King Kong Escapes trying to attack a woman named Susan Watson from th UN. Kong then comes along and kills Gorosaurus by breaking his jaw. This was a relativly short battle and brought Kong little harm. (This scene was uncannily similar to the original scene in King Kong where Kong battles the T-rex and begins and ends in exactly the same way.
The next movie Gorosaurus appeared in was in Destroy all Monsters as another resident of Monsterland. After being put under mind control by the Kilaakians, he was sent to destroy Paris, France. (This scene was originally meant to be for Baragon, but since the suit was in such bad shape from all the T.V. show modifications that it had been put through, they could barely use it in the movie.) In the final battle in the movie, Gorosaurus was one of the most active in the epic battle. His last appearences were in All Monsters Attack and Godzilla vs. Gigan as stock footage from Destroy all Monsters.
Gorosaurus is a tooth and claw kaiju lacking any form of beam weapon or projectile. He can execute an extremely powerful kangaroo kick that can knock even King Ghidorah down. He also has a large jaw which he often uses for biting. In Destroy all Monsters, he burrowed out of the ground in france. This scene was originally scheduled for Baragon who has this ability. As more thouroughly explained in "Movies" the suit was to damaged to use in that scene.
In King Kong escapes, Gorosaurus had a roar that was almost identical to Megalon's. The way Gorosaurus roared though was more distorted than Megalon's roar. In Destroy all Monsters, Gorosaurus used Varan's roar much in the way they used Varan's roar for Showa Baragon also. (Surprisingly, all three appeared in Destroy all Monsters dawning the same roars.)
Gorosaurus has very few collectibles due to the lack of demand for him. Bandai released an early figure of him on the 8 inch scale which is very rare. In thier Gashapon Candy store line, they released a 3 inch version of him along with many other monsters. It was rumored a few years back that Y-MSF would release a figure of him along with Biollante. However, since it has been a few years now, and they have made different monsters, this is begining to seem more unlikely.
Gorosaurus is one of the less popular monsters and has never appeared in a video game or been considered. His lack of popularity may be because of him not being used in a movie or game and his lack of a weapon. However, he is still very popular among collectors due to his rarity. He is still a fairly well known kaiju none the less especially for Showa fans.