Hidden throughout each level are optional strawberries, obtained through challenging platforming or puzzle solving sections, which slightly affect the game's ending depending on how many are collected. Additionally, there are cassette tapes which unlock harder "B-Side" variations of certain levels, and crystal hearts used to access post-game content. Beating all the B-Sides then unlocks the "C-Side" versions, which consists of very hard but short variations upon the levels. Upon clearing all "C-Sides", the player can access the Variants menu (See Game design page for more info). The original Celeste Classic Pico-8 prototype can also be found as a hidden minigame.