The Final Battle (New Super Mario Bros. U)

The Final Battle, or Peach's Castle-2, is the final course of Peach's Castle and it contains the final boss of the game, Giant Bowser (with Bowser Jr. in his Koopa Clown Car). Completing this course unlocks the portal to Superstar Road and Secret Island.

Layout
The first part of the course is a short section comprised of lava and platforms similar to a Spine Coaster. Bowser Jr. will periodically crash into the ground, destroying Brick Blocks and the previously mentioned platforms.

The second part of the course contains the first Bowser battle, which greatly resembles the first part of New Super Mario Bros. Wii's final boss. Hitting the switch at the other side of the course causes an Axe to cut the bridge Bowser is standing on, making him crash into the pit below. After the player moves on to the final part, Bowser Jr. convinces Kamek to enlarge Bowser.

The last part of the course is a boss battle with Giant Bowser. Unlike the three previous encounters, however, the player must directly harm Bowser by stealing Bowser Jr.'s Koopa Clown Car and crashing it down on Bowser's head. After doing this three times, Bowser is defeated and the game ends.

Star Coins

 * Star Coin 1: In plain sight, the player must use the Wall Jump to collect it safely.
 * Star Coin 2: The player must tempt Bowser Jr. into destroying the Brick Blocks above the second Star Coin.
 * Star Coin 3: Much like the first Star Coin, the player must Wall Jump to collect the final Star Coin.

Enemies

 * Podoboos
 * Bowser Jr.
 * Bony Beetles

Trivia

 * The music which plays during the first part of the level is a slightly more evil-sounding remix of the Peach's Castle theme.