The Goliathon is the secondary antagonist in the special Toy Story That Time Forgot. It is one of the battlesaur toys.
Toy Story That Time Forgot
In the Battlesaur mythology, the Goliathon is a beast from the outlands that was captured by the Battlesaurs, put under control by Ray-Gon, and subsequently kept as a fighting beast. According to Head of Story Derek Thompson, it has a "Zeta breath weapon", although this was not shown in the special. The Goliathon has a button on the side of its jaw which activates it. It then becomes aggressive until it has succesfully swallowed something.
When the fight of Reptillus Maximus against Woody and Buzz Lightyear goes awry, The Cleric demeands the release of the Goliathon. Ray-Gon activates it, and it swiftly swallows Woody and Buzz, to the joy of the Battlesaurs and the disgust of Trixie. After the battle, Woody, Buzz and Angel Kitty are retrieved from the Goliathon to be disposed of in "the pit."