World 1-A (New Super Mario Bros.)

World 1-A is an underwater level in New Super Mario Bros.. In the background, there are underwater mushrooms. The level is also auto-scrolling, so Mario will have to be careful. At the beginning of the level, Mario will find himself in a grassy area with some water and a Warp Pipe. If Mario enters the pipe, then he will come out under the water, with some Cheep-Cheeps and Blocks. After this Mario will find several coins in air bubbles floating around the level, and some sharks known as Sushis will attack Mario. A P-Switch is just up ahead, and if Mario presses it, many Silver Coins will appear. In this area, there are several bouncy obstacles. Past this, there is the first Star Coin in the level. Just after this, there is a pipe which Mario can enter to get above the surface, where he will find the second Star Coin. There are also several ? Blocks and Brick Blocks here. After that, Mario will find more Cheep-Cheeps and Sushis, and a Roulette Block. Then Mario will come across a Red Ring, and he will have to be careful while grabbing Red Coins, as the enemies will attack him. Then, there are several pipes which propel Mario up, and he will have to press down because they will make him hit the enemies.

There is then another P-Switch which will make more Silver Coins appear. Then the third Star Coin can be obtained, but Mario must be careful, as he could be crushed between the walls of the auto-scrolling level and the actual walls. After all that, Mario will exit the underwater area with a green pipe, and he will slide down the flagpole.