At the time of the SpellStone crisis, the dinosaur tribes knew of the Krazoa as those who gave stability to the planet.
They exist as six spirits able to pass through walls, and can inhabit someone's body temporarily. The Krazoa could also apparently control dark matter. Andross manipulated General Scales' rise to power and tricked Krystal and later Fox McCloud into gathering the spirits of the Krazoa, using their mystical properties to fully revive himself in a new body.
News of the Krazoa's great powers seemed to have reached the ears of other Lylat planets, as a near death Andross had arrived on the planet, hoping to take advantage of their powers to restore his physical form after his defeat during the Lylat Wars and brief revival four years later. When a courageous young fox girl named Krystal came to the planet's rescue and attempted to release the first spirit, Andross trapped the vixen in a crystal prison, waiting for Fox McCloud to release the other five spirits and bring them there as bait. As Fox returned the first SpellStone, he was contacted by what appeared to be a projection of a Krazoa, who claimed Krystal released it when she accepted its test. It asked him to complete what Krystal started to save her life, accompanied with disturbing telepathy of Krystal's pleas. While it is unclear in-game if this was a genuine Krazoa or Andross impersonating it, the Nintendo Power guide heavily implies that it was the latter. Either way, it is certain that Andross was waiting behind the scenes and was sure that Fox would be willing to perform this ordeal, knowing that the vixen was depending on his success.
Fox was eventually successful in bringing the other five spirits to Krazoa Palace, unknowingly helping trigger Andross' resurrection, as the spirits flew themselves into Krystal's prison. She channeled their power, releasing them into an enormous statue opposite the site of her prison. Eventually the head of the collosus came to life, claiming itself to be the mighty Krazoa God before immediately taking to space. As Fox flew in his worn-out Arwing to face the imposing, suspicious threat, the mask turned around to reveal the same mad scientist he destroyed eight years ago, reborn and eager to destroy the Lylat System. Without a second thought, Fox flew to battle his archenemy once again. With surprise help from Falco Lombardi, Andross was defeated and the six Krazoa Spirits abandoned their ape host, redeeming themselves as they returned to reassemble the shattered sacred lands to the surface of Dinosaur Planet.