List of New Super Mario Bros. U pre-release and unused content

This is a list of pre-release and unused content for the game New Super Mario Bros. U.

Early ideas
Miis were originally going to be playable in all modes, but Story Mode does not support Miis.

Boost Mode was originally known as Assist Mode or Assist Play, as seen in a perspective image below. In early builds, it worked similarly to the final version, except that Blue, Purple, Red, and Green Boost Blocks kept their symbols at all times, and they did not release coins. Instead, a separate Boost Block did that, a smaller one with a coin symbol. These types of Boost Blocks would appear only if the Wii U GamePad player tapped on the screen twice. Boost Mode also seemed to lack the Boost Star and special Boost Mode properties.

Boost Rush Mode has not changed a lot from the earlier builds, except the Coin Meter was below the Coin counter instead of the timer.

In the 2013 Nintendo Company Guide, there is concept art of early designs of Nabbit and the Flying Squirrel suit. Also, the page shows sketches of different Goomba designs and designs of the Acorn Mushroom.

Artwork for the Deep Cheep enemy exists for this game, even though the enemy itself does not appear. They were later included in New Super Luigi U.

Early builds
As shown by the screenshots below, the HUD of the game was originally more like New Super Mario Bros. Wii's, with the white font for everything besides the Coin counter, which had orange instead. Later on, the HUD font was changed to a more opaque and metallic font.

In New Super Mario Bros. U first builds, Warp Pipes had a darker and more metallic-like look, similar to its predecessors. In the final version, they are brighter and have a more plastic look. This look was used in Super Mario Maker 2.

In early builds of New Super Mario Bros. U, the Acorn Plains map looked substantially different. The map was significantly less detailed, the Acorn Trees did not show the Super Acorns, the mushrooms that lead to Mushroom Heights were just red, the map had two red Toad Houses, with the green Toad House in a different spot; there were two Enemy Courses instead of one, and the spot where the Balloon Baby Yoshi was is gone, implying that Baby Yoshis could not be taken into any course or that the option was not programmed yet. A bridge also extended from the level which Yoshi Hill will later become, implying that Yoshi Hill (or the course that was there in the first place) would have had a secret exit that skipped Mushroom Heights and Rise of the Piranha Plants.

Trailer
The version of Painted Swampland shown in the E3 2012 trailer had pipes that were primarily green, while the final version has pipes of varying colors. Another course presented in the trailer was shown an Acorn Plains course with Bubble Baby Yoshi, tilting mushrooms, and Hammer Bros. This course could had been an early version of the Rise of the Piranha Plants course, but otherwise, the course is absent in the final game.

Demo
Acorn Plains Way, Mushroom Heights, and Spinning Star Sky were named Course 1, Course 2, and Course 3 respectively in early E3 builds, presumably to avoid spoiling the world/names.

Acorn Plains Way has gone through various changes since the original showing during June 2012's Nintendo Direct, mostly in the main grassy area. Most noticeably is that the pipe leading to the sky sub-level has been moved further back in the final build and the hidden area near the Checkpoint Flag was much more narrow and shorter in the E3 build. When the player receives a Super Acorn, the sound effect was the normal Super Mushroom sound effect, but the final version's sound effect was varied.

In Spinning Star Sky, Note Blocks had a different sound, different than New Super Mario Bros. 2's in the E3 demo. The E3 demo version's sound effect was a very fast ascending B Major scale. Also the spinning stars were not making a mallet-like sound when spinning.

Baby Yoshis in E3 builds did not have animations for singing, though the vocals could still be heard. Glowing Baby Yoshi in the E3 2012 trailer had the ability to glow brighter when the player shakes the Wii Remote, though a sound effect did not accompany it. Balloon and Bubble Baby Yoshis do not come out of eggs in ? Blocks, unlike in the E3 demo, and are found only in the main map.

In Course 2 and 3, when the player touches the Green Ring, it makes the same ticking sound as the Red Rings, because the final Green Ring ticking sound was different, but it ticks as the same time as the final version's ticking.

When the player clears the course, the part that said "Course Clear" in the demo was all capital letters as "COURSE CLEAR!" but in the final version it appears as "Course Clear!"

Peach's Castle seen in Acorn Plains Way had its colors more faded out in early E3 builds.

Unused data
The first image in the ChallengeImage folder, which contains all of the challenge previews in Challenge Mode, is a sample image of an early version of Acorn Plains. The ground tiles resemble the grassland tiles from New Super Mario Bros. Wii, and the background is less detailed with lower resolution. The shadowed structure in the background is an early version of Peach's Castle sitting atop a large cliff. Unlike the final version, the castle can be seen from the beginning of the stage.

Yoshi drums for jungle overworld theme can also be found in the game's files, but goes unused since Yoshis do not appear in any forest levels in the game. This music is later used in Super Mario Maker 2, where Yoshis can be placed in Forest-themed levels.

Ice Snake Blocks, along with ice variants of large Snake Blocks, are unused in the the game. Frozen Munchers from New Super Mario Bros. Wii are also unused.

There is also a pepper and a star in the game's code. While unknown what they were planned to be used for, they look like a level icon.