Egg Planet

"Egg Planet" is a recurring musical theme that first appears in Super Mario Galaxy, where it serves as the background music for Good Egg Galaxy. It was one of two pieces composed by Koji Kondo for the game, the other being "Rosalina in the Observatory".

Original
In Super Mario Galaxy, "Egg Planet" serves as the background music for Good Egg Galaxy. It is also heard during the ending of the game when Mario and Princess Peach are whisked away with the final Grand Star.

Mario Kart Wii
A portion of "Egg Planet" can be heard in the theme for Mario Kart Wii's Rainbow Road. The arrangement returns in Mario Kart Tour with the debut of Wii Rainbow Road in the 2023 Space Tour.

Mario & Sonic at the Olympic Winter Games
An arrangement of "Egg Planet" appears as a track in Mario & Sonic at the Olympic Winter Games that plays during Dream Ski Jumping events, which take place in Good Egg Galaxy. The arrangement returns as a track in Mario & Sonic at the Sochi 2014 Olympic Winter Games.

Super Mario Galaxy 2
In Super Mario Galaxy 2, an arrangement of "Egg Planet" titled "Green Star" plays on World 1's map after Green Star comets appear.

Fortune Street
In Fortune Street, an arrangement of "Egg Planet" serves as the background music for the Good Egg Galaxy board.

Mario Tennis Open
In Mario Tennis Open, an arrangement of "Egg Planet" serves as the background music for the Galaxy Rally Special Game.

Mario Party: Island Tour
In Mario Party: Island Tour, an arrangement of "Egg Planet" is included in a section of the music for the Rocket Road board.

Super Smash Bros. for Wii U
In Super Smash Bros. for Wii U, an arrangement of "Egg Planet" by Nobuko Toda is included as a track and can be played on the Mario Galaxy stage. The arrangement returns as a track in Super Smash Bros. Ultimate and can be played on any Super Smash Bros.- and Super Mario-series stage.

This arrangement also appears as the fourth track on the blue disc of Super Smash Bros. for Nintendo 3DS / Wii U: A Smashing Soundtrack, a sound selection CD of Super Smash Bros. for Nintendo 3DS / Wii U's soundtrack available exclusively to Club Nintendo members.

Other arrangements
"Egg Planet" was one of the songs performed in the Super Mario Galaxy medley in the Super Mario Orchestra Concert in 2018.