Grumdorf is the planet Al created to harbour his new Spore series and is the homeworld of the Chammi Cham. The planet is also a neighbor, and possibly in the same solar system as Chodarius, home of the Kooboo. The planet is known for the giant brown mushrooms that grow on its surface. The planet is host to much life, most noticeably, the Chammi Chams. Grumpdorf is shown to have one moon like Earth, but it appears to be made of solid gold. The name of this moon is yet to be seen.
Grumdorf is an ice planet, as shown by it's pale blue surface. Similar to Chodarius in it's oceans and continents. The land, however, is mostly ice, and the surface of the planet is dotted with mushroom cloud–shaped rocks, causing Al to dub it "The Fallout World." The planet is mainly 2 large continents, with smaller islands to the north and south.
Grumpdorf is just one planet in the solar system, Selis. The others from closest to their sun, to the the farthest are;
- Bummes: a large red gas giant, Bummes is about 2.5 times bigger than Grumpdorf. Since it is so close to the sun, it must not be made of flammable gases like oxygen, hydrogen, or methane.
- Grumpdorf: (see above)
- Madia: a temperate desert planet very close in size to Grumpdorf. It has a blue sky like Earth and may be habitable. It is shown to be home to a long extinct sentient species, most likely resembling hogs by the look of their skulls.
- (Unknown): a small ice planet far off like Pluto, this planet is about a third the size of Grumpdorf. Its name is yet to be determined.