Peach's Castle (New Super Mario Bros. U)

Peach's Castle is the final area of the main game in New Super Mario Bros. U, New Super Luigi U, and New Super Mario Bros. U Deluxe. It seems to be in the same place as it was in New Super Mario Bros. Wii. However, this iteration has a large moat surrounding the castle (as in Super Mario 64 and other games), an extra floor, as well as two extra towers on either side of the central tower.

In the game's opening, Bowser and his Koopalings once again attempt to kidnap Princess Peach. Bowser throws Mario, Luigi, Yellow and Blue Toad all the way to an Acorn Tree in the Acorn Plains. Afterwards, Bowser sends the Koopalings to secure the land's castles, while Bowser's Airship hovers over Princess Peach's. Over time, Bowser raids and remakes Peach's Castle into his own image, until it is eventually shrouded by a tornado created by Magikoopa.

Like its predecessors, the castle appears in the first level, Acorn Plains Way. However, unlike its predecessors, it's not seen at the start of the stage, as the Acorn Tree takes that spot. Instead, it appears near the end of the stage and even then, it appears very far into the distance. It's also the final, lava-themed world of New Super Mario Bros. U and New Super Luigi U, as at that point, the castle has been fully remade to Bowser's interest. The castle itself remains unchanged from the outside (it has changed on the inside, though), but the ground is charred and is surrounded by a moat of lava. There are six levels, making it the world with the least amount of levels in the game and the only world to not have a Toad House.

At the end of the game, Peach's Castle is restored to its original state. However, if the players play post-endgame, and enter the world, the area will revert back to how it was inside the tornado, except for the flags, as the black Bowser flags are still replaced by the white and pink Peach flags afterwards.

Challenge Mode original courses

 * Mole to Goal Returns - Special
 * Wobble and Rock - Special (Original Course)
 * No Climbing Allowed - Special

Boost Rush courses

 * Meteor Moat - Expert Pack

New enemies

 * Meteors
 * Magmaws
 * Big Buzzy Beetles
 * Flame Chomps
 * Bowser Stunners
 * Parabombs
 * Bowser Jr.
 * Boss: Bowser

Trivia

 * This world, along with Rock-Candy Mines and Superstar Road, is one of the only three worlds in both games to not have Enemy Courses.
 * This is one of only two worlds in both games (the other being Superstar Road) that has no direct path to or from Soda Jungle.
 * The world's music is a sinister-sounding arrangement of "Inside the Castle Walls," the music heard inside Princess Peach's Castle in Super Mario 64.
 * This world is also the only one to have different music from previous worlds, which use the same melody with slight variations reflecting the world's themes.
 * The music was later remixed as the background music for World 8 in Puzzle & Dragons: Super Mario Bros. Edition.
 * Peach's Castle being transformed into a citadel for Bowser had occurred earlier in Super Mario Bros.: Peach-hime Kyushutsu Dai Sakusen!.
 * Peach's Castle being transformed by Bowser is similar to the castle being taken over by Shroobs in Mario and Luigi: Partners in Time and Fawful in Mario & Luigi: Bowser's Inside Story and its 3DS remake (though it is more exaggerated in the remake of the latter game).

Pilz-Palast Castello di Peach (New Super Mario Bros. U)