World 2-Castle (New Super Mario Bros.)

 is the last level and the castle of World 2. The boss here is Mummipokey.

Layout
The level starts out with the player standing beneath a shallow stairway of Brick Blocks. A Giant Spiked Ball quickly destroys the Brick Blocks. The Giant Spiked Ball rolls onto the next platform, and then falls into an abyss. The player can then safely jump across the first abyss, where they can grab three coins that are floating over the abyss. The player will find a ? Block that contains a coin inside of it, right next to another abyss that has three more coins floating over it. The player can collect the coins as they jump across the abyss. Past the abyss, the player will encounter many normal-sized Spiked Balls. The player can find another ? Block that contains a power-up. Eventually, the player encounters a divot that contains another Giant Spiked Ball. Above this Giant Spiked Ball is a rope, which the player can use to swing over the divot to avoid the Giant Spiked Ball. By swinging and landing low, the player can collect six coins and continue forth in the level. If the player swings and lands high, they gain access to a previously-unseen group of platforms. These platforms host about thirty coins, and a ? Block containing a 1-Up Mushroom. Farther to the right, the player sees three more ? Blocks, two of which contain coins, and the third containing a power-up. Past the ? Blocks, the player has to crouch down into several small divots, or jump onto higher platforms to avoid being harmed by rolling Spiked Balls. The player eventually sees a Star Coin that must be accessed via the use of a few Wall Jump, while avoiding another Spiked Ball. On the opposite side of the abyss, the player encounters another Spiked Ball, followed by a door that leads outside to the desert.

Outside of the castle, the player encounters many Bullet Bills and Spiked Balls. They must avoid multiple obstacles and traps to make it to the other side of the grounds, where they gain access to the inside of the castle through double doors. The last two Star Coins can be received outside. One must be retrieved by jumping on a Bullet Bill to reach a high crevice, while the other can only be accessed via the use of a Mini Mushroom. A Mini Mushroom can be found in the level if the player swings on a rope and lands high on a platform. At the end of the grounds, the player must press a ? Switch which lowers the ground, allowing access to the door that leads to Mummipokey.

Once the player defeats Mummipokey, the player will gain access to a new world. If Mummipokey is defeated while Mario is in his Mini Mario form, he will gain access to World 4. If Mummipokey is defeated by any other means, the player will gain access to World 3.

Star Coins

 * Star Coin 1 - After venturing through some of the level there will be a location high above. Using Wall Jumps, Mario should get to the location and avoid the Spiked Ball that comes. The Star Coin should be able to be accessed by a small crevice.
 * Star Coin 2 - Mario should hop off a Bullet Bill outside the castle, or jump to it as Mini Mario.
 * Star Coin 3 - Mario should become Mini Mario and enter the small crevice in the steps near the end of the level, where the third Star Coin can be found.

Enemies

 * Giant Spiked Balls
 * Spiked Balls
 * Bullet Bills
 * Bill Blasters
 * Mummipokey (boss)

Trivia

 * World 2-Castle is one of the only three castles in the game that partially take place outdoors (the other two being World 6 and World 7, where the boss battles take place outside).
 * World 2-Castle is one of the two bosses where a cutscene always plays, after defeating the boss. This is so the player knows how to unlock world 4.