World 1-2 (New Super Mario Bros. 2)
From the Super Mario Wiki
The level starts off with a green Warp Pipe. Above it is a green Koopa Troopa enclosed in Brick Blocks and the first red POW Block. Hitting the block will destroy the Brick Blocks and overturn the Koopa. The POW Block itself turns into a Empty Block. Another POW Block is found to the left of the area, and reveals coins behind Brick Blocks when hit. Going down the pipe, the player will automatically ground pound and hit another red POW Block. The level is full of Koopa Troopas and red POW Blocks, which break empty Brick Blocks, trigger those containing items or reveal hidden items. Mario will then come across several Brick Blocks where the player can see three Koopas and two POW Blocks. A gold Warp Pipe that Mario can enter soon follows. A Piranha Plant can be seen in the next gold pipe. After the moving platforms, the player can see the first ! Pipe. To access it, the player needs to use a Koopa to activate a POW Block. Exhausting the pipe will release a Mega Mushroom. After several more Koopas and Piranhas, the player reaches the checkpoint flag. Mega Mario is needed to break several blocks to obtain another Star Coin between two sets of moving platforms. After that, a pipe leads back to the overworld, where another set of Brick Blocks can be found with a POW Block, followed by the flagpole.