New Super Luigi U

New Super Luigi U (styled as New Super Luigi Bros. U) is an expansion pack to the Wii U title New Super Mario Bros. U, released as part of The Year of Luigi. It features Luigi as player one, with Yellow Toad, Blue Toad, and, notably, Nabbit (who replaces Mario from the original game) playable in multiplayer mode. Features like Challenge Mode and Boost Rush are not available.

The title was released for the Wii U eShop, and can be purchased by accessing it via an Internet connection, and having a copy of New Super Mario Bros. U. Once downloaded, the player must press a certain button on the file select screen to play. It will also be available for purchase at retail. This version will not require New Super Mario Bros. U in order to be playable. Wii U Pro Controller support will also be included in addition of Wii Remote and the Gamepad controls in New Super Mario Bros. U. This game is also to be released at retail as a standalone game, not requiring New Super Mario Bros. U.

Gameplay
The gameplay is largely similar to its base game, except that the playable characters retain Luigi's higher jump and lower traction from Super Mario Bros.: The Lost Levels. The game itself is also made harder, and every course starts at one-hundred seconds. Elements like Items, Power-Ups, Star Coins, Toad Houses, Enemy Courses, and bosses are retained.

Playable

 * Luigi
 * Yellow Toad
 * Blue Toad
 * Nabbit

Changes
The world map itself is unchanged from New Super Mario Bros. U and level designs have had a drastic makeover, making them much harder. As mentioned above, playable characters and their abilities have changed. The timer for each level is also set to start from 100 seconds and the 100-seconds time bonus are added to the timer after going to the boss door in the towers and castles. Items in red Toad Houses may vary as well. For example, a 1-Up Mushroom is in place of a Super Mushroom. Similarly, Enemy Courses have random power-ups such as Mini Mushrooms and Propeller Mushrooms as opposed to only Stars. Also, many elements of the the game are colored green to emphasize Luigi. There are also no checkpoints, which make it really hard.

After the game is completed, a red "M" block appears at the beginning of levels. This allows the player to switch to the original game's physics, with lower jumps and better traction.

Worlds
There are 82 new courses replacing the original courses from New Super Mario Bros. U with different level names, though the world names are retained.
 * Acorn Plains
 * Layer-Cake Desert
 * Sparkling Waters
 * Frosted Glacier
 * Soda Jungle
 * Rock-Candy Mines
 * Meringue Clouds
 * Peach's Castle
 * Superstar Road

Trivia

 * In the opening scene, Mario's Cap is seen on the table of Peach's Castle.
 * The artwork used on the box for the game uses the Soda Jungle background, but the foreground uses the Sparkling Waters theme.
 * In some of the levels, 8-bit Luigis are found.
 * Even though Nabbit helps Luigi is multiplayer mode, Nabbit still steals items from the Toad Houses, and the player will have to catch him. This means that Nabbit can catch himself.