Tyrant was created by the combined spirits of several Kaiju that were defeated in the past by the Ultra Brothers. After leaving Neptune and heading towards Earth, Zoffy was the first to attempt to stop Tyrant only to be easily defeated by the chimera Kaiju's combined strength. From then on, Tyrant would face off against the other Ultra Brothers on the other planets that were to come after Neptune - Ultraman on Uranus, Seven on Saturn, Jack on Jupiter, and Ace on Mars, and like Zoffy they were all met by Tyrant's superior strength and were beaten down with ease by the behemoth all while ZAT was tracking the Kaiju's movements from their base.

Fortunately, while Tyrant had erased each of the Ultra Brothers' Ultra Signs on the route to Mars to stop them from contacting Earth, he was unable to stop Ace from using his to warn ZAT and Taro of Tyrant's presence. Finally, Tyrant arrived in Japan and immediately began attacking, wreaking havoc across the city. ZAT was quick to attack but was not enough to match Tyrant's strength. Kotaro turned into Ultraman Taro shortly after and the two fought.