From the Super Mario Wiki
The Underground Maze is the third level of Adventure Mode in Super Smash Bros. Melee. It is based on The Legend of Zelda series. The fighter's goal in this stage is to find the Triforce, hidden in one of five Battlefield-like areas in the maze. The artifact's location is random each time Adventure Mode is played. Fighters must also watch out for ReDeads, Octoroks, and Like Likes. If the fighter comes across a battle area without the Triforce, they will have to fight Link and KO him to proceed.
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