Endless Mine Zone is an underground-themed Zone and has numerous similarities to Mystic Cave Zone and Lava Reef Zone. It features a dark cave background with purple rocks similar to the ones from Lave Reef Zone, while the Zone's rocks are green and yellow with wooden structure forming paths.
Gameplay
At the starting point, items from the Competition Mode are floating around the hall. When the player is bounced away by a red spring, he/she has to break through yellow colored piles of rocks by using the Spin Jump or Spin Attack in order to go down.
After that, the Zone starts overlapping and the player has to pass through a U-shaped gap and get to the right route. If the player has too much speed while running or performing the Spin Attack, he/she will fly forward through the Zone and fall down after hitting a wall, losing precious seconds in the meantime. It is therefore recommended to run through the U-shaped section at a suitable speed. The player then has to run through a shuttle loop to get back to the starting point of the Zone.
Trivia
Because the song for this Zone is the major basis for it, in the console/PC releases of Sonic Generations, a small piece of the Zone's music is sampled in the second verse of the Classic remix of "Escape from the City".
While visiting this old mine shaft, use your Spin Dash attack to smash rocks in order to clear your path. 
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