Jack Shindo and Stanley Haggard are members of the first manned expedition to Mars, and on the red planet find a giant slug-like monster, Goudes/Gudis. Shindo is pinned by a rockslide and Haggard tries to escape in their ship but is blown up by Gudis. Suddenly a giant warrior, Ultraman Great, arrives and fights Goudes, but when Ultraman is on the verge of victory Goudes changes into a virus and travels to Earth where it mutates other creatures into monsters and awakens existing ones. Needing a human host to survive on Earth, Ultraman joins with Jack, allowing him to become the mighty alien when all seems lost. He joins UMA in order to help them battle the monsters.
Signs of Life
The Hibernator
The Child's Dream
The Storm Hunter
Blast from the Past
The Showdown
The Forest Guardian
Bitter Harvest
The Biospherians
Tourists from the Stars
The Survivalists
The Age of Plagues
Nemesis
Chōjin Sentai Jetman
Mighty Raju
Spider-Man
Yu-Gi-Oh! Duel Monsters
The Sandman
SAINT SEIYA: Knights of the Zodiac
Astro Boy Reboot
Turning Mecard W
Dogengers
GARO
Loonatics Unleashed
Mirai Sentai Timeranger
The Batman
Madan Senki Ryukendo
Justice League
Supernatural
Heroes
Fantastic Four
Spider-Man: The New Animated Series
Space Sheriff Shaider