Thread:ITVdude2000/@comment-12498802-20170316170326/@comment-12498802-20170327195308

Nope. All levels are mandatory, but they're set up in this way...


 * Tree Town Set A: 1
 * Tree Town Set B: 2, 3, 4
 * Tree Town Set C: 5, 6, 7
 * Tree Town Set D: 8, 9, 10
 * Tree Town Set E: 11
 * Eager Exploration Set A: 1, 2, 3, 4
 * Eager Exploration Set B: 5, 6, 7, 8
 * Eager Exploration Set C: 9, 10, 11
 * Eager Exploration Set D: 12
 * Aqua Alley Set A: 1, 2, 3, 4
 * Aqua Alley Set B: 5, 6, 7, 8
 * Aqua Alley Set C: 9, 10, 11
 * Aqua Alley Set D: 12
 * Magma Mountain Set A: 1, 2, 3
 * Magma Mountain Set B: 4, 5, 6, 7
 * Magma Mountain Set C: 8, 9, 10, 11
 * Magma Mountain Set D: 12

Complete all stages in a set to unlock the next set. Aqua Alley 11 is unlocked by completing Aqua Alley 9, while Magma Mountain 11 is unlocked by completing both Magma Mountain 8 and Magma Mountain 10.