World 1-A is a secret level of World 1 from New Super Mario Bros. 2, and it's themed around Warp Pipes. It has many Koopa Troopas, Piranha Plants, and Flippers. In order to access this level, you have to buy it after completing World 1-4.
This level takes place in a maze of pipes, making it similar to Pipe Land from Super Mario Bros. 3. It contains one-way flippers from New Super Mario Bros., pipes that launch Mario and a few Gold Rings to grab many coins from golden enemies. At the end of the stage is the Flag Pole, which is set past four Piranha Plant-infested pipes that can be used to grab the tip of the pole.
- Star Coin 1: Not too far into the level, you'll see a Flipper blocked off by Brick Blocks. Ground Pound these Brick Blocks (Small Mario is unable to access this), and it'll reveal this Star Coin.
- Star Coin 2: At the part where you go down through Warp Pipes while dodging Piranha Plants, this Star Coin will be in plain sight, though it will be blocked off by a Flipper. Move a little bit to the left, but not past the Flipper under you, to open the Flipper blocking off the Star Coin. Then grab the Star Coin.
- Star Coin 3: Right before the Flagpole, hit a Hidden Question Block in between the Warp Pipe staircase and the floating Warp Pipes. Then go into the Warp Pipe to the left of the Hidden Question Block. This will lead you to a room with a Big Piranha Plant, a red Koopa Troopa, and the Star Coin. Use the red Koopa Troopa (or Fireballs) to defeat the Big Piranha Plant, and reveal the way to the Star Coin.
- Koopa Troopas (green and red)
- Piranha Plants
- Goomba Towers
- Big Piranha Plants
- Green Koopa Paratroopas