This Herculean monster lives in a place known as “Japan’s Bermuda Triangle,” a mysterious realm that appeared alongside a rainbow.
It has a cruel and ferocious personality, and is covered in tough, silver skin.
It possesses immense strength but has poor eyesight and can only see moving things.

As it was attacking a car of people that happened to be lost in the area, Barrier Monster Gagi II entered the fray.
Silvergon broke a hole in its barrier and began to fight.
After tearing off Gagi II’s arms, it used them to restrain it and ripped open its throat with its teeth.

Daigo Madoka of GUTS, who had also become trapped in the mysterious realm, transformed into Ultraman Tiga.
It looked as if Silvergon would win at first, but things turned around after Horii told Tiga of its weak point.
Finally, Tiga transformed into Power Type and defeated the monster with Tiga Burning Dash.