Spectrobe Masters are people that are chosen by the Spectrobes themselves, and utilize the beasts in the use of protecting the universe.
Spectrobe Masters are the only ones that can awaken the Spectrobes with their voice and command them in battle. They will not respond to another person's commands, with the exception of the master's partner.
"There is a special bond between fossils and Spectrobe Masters. The creatures live with their master, fight alongside them, and when the master passes away, their Spectrobes fall back into a fossilized state until the next master comes along. They are passed down from master to master, like some ancient teaching.
When a Spectrobe falls back into slumber, they sometimes take with them special memories and messages from their former master. When another Spectrobe Master comes in contract with the fossil, the Spectrobe can sometimes show them the memory through a flashback or sorts."
Kentaro Hisai. Producer. Disney Interactive Studios (Japan)
In ancient days the Krawl suddenly began an giant invasion which was focused mainly on the Kaio system, and the planets there, Wyterra, Doldogo, Kogoeria, Menahat, and Slayso. Here every Spectrobe Master of the system stood up to protect the system and the planets, and many of them sacrifced their lives for the love of their home. 100 Masters aided by 10,000 Spectrobes took up the battle and fought the Krawl back, thus saving their system. On Menahat a Legendary giant fish Krawl known as Zabacraw fell down on the planet and then made a crater known as the Pit of Ruin. At Menahat, seven sets of ruins could be risen from the sands of the Great Desert in order to be used for trapping and defeating the Krawl fish. A legendary white flying Spectrobe, which used to be ridden by people, fought this Krawl. Its name was Pegatinum. At the planet of Slayso, a giant tower was made to serve as a memorial of the giant Krawl War. From the top of it, you can look up and get a fantastic view of Menahat, the desert planet, which long ago was said to had been even greater than Wyterra, with giant cities, towns and buildings. On top of the tower are three white-blue parabolas, one of which is destroyed, and the blue dish is gone as well.