Board Thread:This is Fun/@comment-5340677-20140211001800/@comment-5429417-20140215031831

Isle Delfino is correct! Also would've accepted Delfino Plaza. Here is why Isle Delfino is the answer:

1. It is only visited in Super Mario Sunshine. However, you can also visit it in Super Smash Bros. Brawl by playing on it's course.

2. It is the main hubworld for Super Mario Sunshine meaning you can access all of the other locations from it.

3. It starts out dim due to the lack of Shine Sprites but as you collect more of them, it gets brighter again.

4. After you beat the game, you can leave Isle Delfino/Delfino Plaza by boat and head to Delfino Airstrip.

5. It is home to the unique Piantas.