Spiral Bridge (2in1)

Spiral Bridge is a reconstruction of the level of the same name in vanilla Super Monkey Ball 2. It is the 21st stage of Expert and the world introduction for the Desert world.

Description
The stage is a large spinning circle platform with a thick ascending spiral in the center. The top of the spiral has a long, flat platform that juts outwards, which will align with a floating L-shaped platform that has the goal on it every 10 seconds. The player starts on a small rectangular platform below the goal.

Goal tutorial
The level gives five opportunities to make it to the goal platform. Get onto the large circular platform and advance towards the base of the spiral. Because the set piece is constantly rotating, this will create inertia that will attempt to cause the ball to slip off. It's recommended to climb up the spiral bridge at a moderate pace: If you go too slow, the camera will face backwards, which will make it really difficult to reach the summit of the spiral. Once you're at the top, slowly move towards the end of the straightaway, making sure not to let the inertia send you off. When you're at the end, just as the bridge is about to align with the goal platform, head towards the platform and pull right to stick the landing, then go to the goal.

Differences from vanilla
The starting bridge has been simplified to a small, simple rectangle. The starting position is also closer, making it notably easier (but not entirely free) to make it to the goal platform on the first possible cycle, which is one of the hardest speedrunning strats in the vanilla game. The goal platform also has a bit of extra geometry to support the hieroglyph trims that is seen in most Desert stages in SMB1.

Glitches
If the player rolls between the large circle and the underside of the spiral bridge, the ball will completely phase through the large circle and fall out of the stage.

Trivia

 * This was the first stage made for SMB2in1, being created on February 21st, 2019.
 * This stage was successfully put into SMB1, but is likely only emulator only as when played in Dolphin, it spits out a bunch of errors in the console. The reasoning for this is unknown.
 * There are two copies of this stage in SMB2in1's debug files. The first one, 099 ("no haze :O"), has a broken background. The intention of "no haze :O" was to figure out a way to work around the Desert world having a haze effect, which, while it's perfectly fine in 4:3, blends in terribly with the actual camera if the game's aspect ratio is set to 16:9 or Letterbox (click here to see this bug in action). A way to disable this effect entirely has since been found. The second one, 114 ("spiral bridge"), is a Banana Island reconstruction of this stage, complete with a mirror surface and glossiness to the materials to make it match Banana Island's aesthetics more closely. This particular version was meant to test out new features to GxModelViewer that were added by programmer "The BombSquad".
 * For some reason, the collision glitch mentioned above is patched in the Banana Island version of Spiral Bridge.