The first floor of the castle is accessed from the Castle Grounds. It contains Bob-omb Battlefield, Whomp's Fortress, Jolly Roger Bay, Cool Cool Mountain, The Secret Aquarium, The Princess' Secret Slide, the Castle Courtyard, Bowser in the Dark World, and Tower of the Wing Cap.
The First Floor also has doors leading to the Second Floor and Basement, but they can only be unlocked with keys gained by defeating Bowser.
Courses[]
| Painting | Course | Description | |
|---|---|---|---|
| 1 |
|
Bob-omb Battlefield | This is the first course in the game. It is a grassy battlefield with a mountain that Big Steelies roll down. On its summit, the Big Bob-omb can be fought as a boss. The main enemies are Bob-ombs (as they name would suggest), as well as Goombas. Chain Chomp also guards a star here, and this is the first course in which Mario can race Koopa the Quick. |
| 2 | 
|
Whomp's Fortress | This course is a floating island with a large brick structure on it. Whomps, Thwomps and Piranha Plants are the main enemies here, with King Whomp as the boss of the stage. This is also the only course in which Bullet Bills appear, having a very minor role. Hoot can also be encountered here. |
| 3 | 
|
Jolly Roger Bay | The first water level in the game, as well as the first with a sub-level. Jolly Roger Bay centers around a sunken pirate ship that Mario can enter, draining the water inside and raising the ship to change the geography of the level. Unagi the Eel is found here. Notable, Jolly Roger Bay has a different painting in the Japanese version of the game from in the US and PAL versions. |
| 4 | 
|
Cool, Cool Mountain | Cool, Cool Mountain is a cold, mountainous course where Mario can meet Penguins while avoiding enemies like Mr. Blizzard and Spindrift. Unlike most mountainous levels in the game, Mario starts at the top and must make his way down to the bottom, instead of trying to reach the summit from the ground. Cool, Cool Mountain also has a slide sub-area where two different stars can be obtained. |
| - | 
|
The Princess's Secret Slide | This is a secret stage consisting of an orange slide. Mario can get one of the castle's secret stars at the bottom, or get another by sliding down very quickly within a certain time limit. |
| - |
|
The Secret Aquarium | This is a secret stage, and the only level the the game that is entirely underwater, with no land or even air available. As Mario cannot surface to breathe, he can only survive by collecting coins from the aquarium. Collecting 8 of them grants one of the Castle's Secret Stars |
| - |
|
Tower of the Wing Cap | This is a stage that takes place in the sky, atop five towers that extend down out of sight into the blue void. Mario can unlock the Wing Cap here using a Cap Switch, and collect one of the castle's secret stars by collecting 8 red coins. |
| - | 
|
Bowser in the Dark World | The first Bowser world, taking place in some kind of enormous cavern based on the level background. The actual course in a series of floating platforms along a linear path. Bowser is fought as a boss here, and once he's defeated, he will give up the key that allows Mario to access the Basment |
