CELESTE Classic is a platforming game developed by Maddy Thorson and Noel Berry in 2015. The game, created in the span of four days for a game jam on the PICO-8 fantasy console, has the player control a red haired girl as she climbs Mount Celeste. It received a good amount of attention for its solid gameplay and has had an active speedrunning scene since then. Its success would eventually inspire both creators to expand upon this concept, which led to the creation of the 2018 game.

FlyingPenguin223, RichConnerGMN, cominixo, ikuyo, Meep, Snoo23, gonengazit, Lord Snek, Akliant, Beeb, Warspyking and RoundUpGaming climb the mountain in a record in-game time of 1:34.933.

The second set of encodes were done on a modified version of the game that removes the screenshake effect that's normally present.