The Secret Island (Japanese: シークレッ島 Secret Island) is an island dig site in Fossil Fighters to the Southwest of Vivosaur Island.
You first come here because the five Idolcomp fragments picked up by the Secret Lab radar weren't enough.
Dr. Diggins and Richmond discovered this island and kept it secret because of the crashed Dinaurian spacecraft they found there. They made it undetectable with radar to keep it safe so no one would find it and abuse the technology.The technique of fossil revival was created by modifying the Stone Sleep technology found within.
You go there with Duna because Mr. Richmond thinks that because it is undetectable, the last Idol fragment may be there.
You find a few stone slabs with writing on them that you eventually figure out were written by Dr. Diggins while he was trapped in the late Mesozoic Jurassic period.
They detail the troubles on his long and difficult journey to the island because he knew he could put himself in Stone Sleep and be recovered later. You eventually come into the final room, where you find a fossilized Dr. Diggins holding the last Idolcomp fragment.
At that moment, Raptin comes in and tries to take the fosilized Dr. Diggins and the Idolcomp fragment. You challenge him to a fossil battle. When you win, he runs away and you return successfully to Vivosaur Island. Afterwards, Secret Island can be accessed as a normal dig site.
When the Main Game is completed, Holt may be battled in the final room.
Vivosaurs in this Dig Site