From Sonic Retro
The Little Planet only appears for one month of every year, in the skies above Never Lake. The planet hosts the Time Stones, gems that are coveted by Dr. Eggman due to their mystical ability to control time. Eggman chains the Little Planet to a giant rock (engraved with his own face, no less) and quickly begins work to transform the entire planet into his new base, using time travel to take over the past and thus control the future.
Seeing this, Sonic sets off to foil his nemesis' latest scheme, and eventually sets the Little Planet free by destroying Eggman's base and the rock which the planet was chained to. Released, the Little Planet rises up for a short distance, then completely vanishes. However, if the player gets the bad ending, then the Little Planet is chained back to the rock thanks to Eggman having succeeded in grabbing the Time Stones.
The US instruction manual adds that the Little Planet is normally covered with lush vegetation including tall trees and flowers, but at the start of Sonic CD has been metallised by Dr. Robotnik, and as such is covered only in grim, grey steel.
Other game appearances
The Little Planet is featured again years later in Sonic the Hedgehog 4: Episode II. In Episode Metal, the Little Planet comes close enough to Sonic's world for Dr. Eggman to revive Metal Sonic and have him travel across space and back to his base in Mad Gear Zone for repairs.
Over the course of Episode II, the Little Planet can be seen in the night sky, and as Sonic and Tails progress, Dr. Eggman slowly builds a brand new Death Egg known as the Death Egg mk.II around it. By the time Sky Fortress Zone is cleared, its construction is completed, Sonic and Tails finally reach it and together they destroy Dr. Eggman's final machine. Though they destroy the Death Egg mk.II, it is still intact, and Little Planet is left inside. As the Sonic 4 saga ended prematurely, one can either assume the Death Egg mk.II is eventually dismantled, or the Little Planet is stuck inside indefinitely.
The Little Planet is once again featured in Sonic Mania, and is visited twice by the heroes during the course of the game. The first instance the heroes go to Little Planet is when Dr. Eggman uses the Phantom Ruby at the end of Press Garden Zone to displace the heroes, sending them to Stardust Speedway Zone in the Past.
The second instance that the Little Planet is visited is near the end of the game, as it is visible from Lava Reef Zone on Angel Island. The heroes then travel to the Little Planet for the last two zones in the game, Metallic Madness Zone and Titanic Monarch Zone. In the normal ending, the heroes escape the Little Planet and watch Titanic Monarch Zone explode, while in the true ending, only Tails and Knuckles escape as the Little Planet is again set free from Eggman's control and transported away by the Phantom Ruby.
In other media
In Sonic the Comic, the Little Planet was consistently referred to as the Miracle Planet, save for a single mention in the backup Sonic's World story of Issue #25 ("Prologue: Once Upon a Planet...") that some people know it as the Little Planet. It first appeared in the adaptation of Sonic CD, and then made recurring appearances throughout the series. In this continuity, the Miracle Planet appears in the sky over Mobius for three days out of every month, rather than for one month a year.
In its first appearance, Dr. Robotnik cyber-formed the entire Miracle Planet to be used as a power source for Metallix by somehow transporting a "living" machine to the planet, which then grew to cover the entire planet in grim steel. Sonic managed to defeat Metallix and restore the planet to normal by using a Time Stone which he stole from the machine in the past.
Some time later, the Miracle Planet was taken over by the Brotherhood of Metallix and was again covered in machinery, this time by capturing Grimer and forcing him to build the Alpha Device which in turn transformed the planet, making it appear like a giant Metallix head, and used as a staging ground for the Metallix's attempts to conquer Mobius. Their plans were thwarted by Sonic and the Chaotix, and the Miracle Planet was subsequently returned to normal yet again.
|Locations in the Sonic the Hedgehog Game Series|
|Islands||Christmas Island | South Island | West Side Island | Angel Island | Cocoa Island | Flicky Island | Prison Island | Onyx Island | Southern Island|
|Landmarks||Never Lake | Mount Mobius | Emerald Shrine | Tails' Workshop | Babylon Garden | Gaia Gate|
|Regions / Nations||Eggman Empire | Station Square | Mystic Ruins | United Federation | Central City | Soleanna | Monopole | City | Mystic Jungle|
|Vessels||Death Egg | Death Egg II | Egg Carrier | Space Colony ARK | Eggman Fleet|
|Planets / Planetoids||Mobius | Little Planet | Black Comet | Interstellar Amusement Park | Lost Hex|
|Dimensions||Special Stage | Maginaryworld | Sol Dimension | Arabian Nights | Twilight Cage | Grand Kingdom | White Space|