Eye Spy

"Eye Spy" or "The Lost Planet" (ロスト・プラネット) is the 74th episode of Sonic X

Plot
Everyone is surprised after they land on a deserted planet. Cosmo is knocked out while the team discover that Cosmo's brain is emitting a signal to the Metarex, they plan on trying to eliminate the signal, except that the signal is connected to the part of her brain that translates sounds and sight; thus, Cosmo will most likely lose her eyesight and hearing if the chip is removed. While Tails and Chris are torn about this, Knuckles pushes for the surgery. Meanwhile, Amy starts searching for Sonic, but ends up bumping into Rouge. They both discover that this planet is not only Cosmo's homeworld, but the Metarex's as well. They also discover that Cosmo's people were able to transform into huge dinosaur-like beings to protect their planet from an alien invasion. However, a few of them wanted to be able to completely destroy the alien horde, and so crystallized the Planet Egg in order to keep the transformation from sapping their energy. They eventually led to the abandonment of the planet. Cosmo, horrified by the fact that the Metarex are using her to spy on them, intends to leave, but Tails reassures her that they all will help her defeat the Metarex. Sonic and the rest of the gang also support the new resolution, and they all are ready for the final attack on the Metarex. Shadow is disgusted by this and tries to leave. Chris tries to tell him that he needs to help them, yet he keeps refusing, but then Bokkun arrives, telling Shadow that Eggman has been captured by the Metarex. At the same time Dark Oak has 7 Chaos Emeralds and preparation for Forestation is about to begin.

Trivia

 * Extra Scene:In the Japanese Version After Knuckles knows about Cosmo's people as same as Amy and Rouge, he doesn't understand why the same clan has a different reason to make something correct.