The Special World is a hidden bonus world accessible only to the most dedicated of seekers. In order to reach it, one must find the secret exit in Star World 5. The world is completely linear, having no secret exits or branching paths; it consists of all 8 levels strung out in a row. These levels are arguably the hardest in the game, provided to give a little extra challenge to the player who has managed to clear the regular levels. The reward for completing the Special World is a massive pallet change on the overworld, as well as changes to common sprites (for example, Bullet Bills change to Pidgits).
The Special World contains the following 8 levels:
- Special World has one of the only two ice-themed levels in the entire game, Awesome. The other is Donut Secret 2.
- All of the levels in this world are named for some type of surfer slang (Gnarly, Tubular, etc.).
- Tubular is known to be one of the hardest levels in the entire game, if not the absolute hardest.
- If you stay on the overworld until the music has played a total of 8 times, the original Super Mario Bros. theme will begin to play about 4 seconds into the 9th playthrough (or after 1 minute, 57 seconds).
- A shortened version of Groovy is the level used on the title screen.
- Oddly, the four-color symbol at the top is none other than the Super Famicom logo. One has to wonder why this wasn't changed into something less obscure.