Cascade

Cascade[1] is a location that appears in the anime series Sonic X. It is a planet that exist within Sonic's home universe. It is home to a different group of humans, who appears to be several times more technologically advanced than even those on Sonic's planet, who are in turn more technologically advanced than the humans on Earth.

History
At first, Cascade was once a beautiful planet. It had an empire throughout space made by ruthlessly attacking and conquering other worlds. They had almost conquered the entire galaxy, having countless wars against other worlds, conquering and dominating them, they were in charge of the space-marine empire for several centuries. Fortunately, when the Metarex came and stole the Planet Egg, this caused the planet to slowly die, and Cascade eventually lost its empire.

Anime
Cascade was once a beautiful planet. However, one day the Metarex came and stole the Planet Egg, causing the planet to slowly die. A Resistance fought Pale Bayleaf, in hope to make Cascade beautiful again. Two of the Cascade Resistance were Molly and Leon.[1]

Dr. Eggman and his crew eventually arrived at Cascade during a fight. There, Shadow saved Molly, causing her to believe he was the spirit of Black Wind. However, her hope vanished when Leon and the rest of the Resistance gave up.[1] Molly was soon after killed by Pale Bayleaf[2] and Shadow, using the power of the white Chaos Emerald, got revenge by smashing Pale Bayleaf's ship. Shadow built a grave to Molly using debris and gave Rouge the Chaos Emerald, leaving them to fight the Metarex alone. Later on in the series, Leon and the rest of the resistance were captured by the Metarex, and put into trees. They were consumed by the trees, merging with them and becoming one with the trees. This caused them to slowly die, as the Metarex were using them for a forestation test or something like that. This means there are no more inhabitants of Cascade, and that the people of Cascade are now extinct.

After the Metarex's destruction, the Planet Egg returned to the Planet, making it beautiful once again. Shadow was later seen coming back and placing a rose on Molly's grave.