| ... | ... | |
|---|
| 17 | 17 | |
|---|
| 18 | 18 | Set 2 includes Worlds 7–12, for a total of 6 worlds. The levels of Set 2 are harder than those of Set 1, but are easy enough with sufficient pratice. |
|---|
| 19 | 19 | == Xtra Levels == |
|---|
| 20 | | Xtra levels don't have unique titles, and follow the naming format of \''''World X_'''\'.[* Collaboration levels are an exception.] |
|---|
| 20 | Xtra levels do not have unique titles, and follow the naming format of \''''World X_'''\'.[* Collaboration levels are an exception to this.] |
|---|
| 21 | 21 | The blank is filled with a single letter, which is usually taken from the song title of the boss level. Normally, the first level is used[* e.g. [[World XO]] - '''O'''ne Forgotten Night], but certain titles have overlapping first letters, causing subsequent letters to be used instead[* e.g. [[World XT]] - Op'''t'''ions]. |
|---|
| 22 | 22 | |
|---|
| 23 | 23 | === [[/Xtra Island|Xtra Island : Xtra!]] === |
|---|
| ... | ... | |
|---|