It is speculated, but unconfirmed, that Fungus Forest was an earlier incarnation of Clanker's Cavern. This is due to pre-release footage of the game from E3 1997, showing Banjo and Kazooie swimming around an organic version of Clanker in a temperate environment featuring rocks and grass. The music from Fungi Forest in Donkey Kong 64 plays in the background during this segment of the video. The nearby jigsaw puzzle chamber for Click Clock Wood may also have had some relation to Fungus Forest, as it features textures that are not found in Click Clock Wood, but are used in Fungi Forest in Donkey Kong 64.