World 5-2 (New Super Mario Bros.)
From the Super Mario Wiki
Ads keep the MarioWiki independent and free :)
This level is another underground cave where ice covers the ground. The level contains multiple Spike Tops and Swoops in it. To get the first Star Coin, Mario should go up, avoiding the Piranha Plants, and then he should hit blocks above him. After the Piranha Plants are two Warp Pipes, one yellow, and one red. The player should go ahead to an area with a Springboard, and above it is the third Star Coin. Mario should get the Star Coin and move the Springboard to the yellow and red pipes seen earlier. If the player jumps into the yellow one, they will go to an area with a Moneybag. Mario should go to the end to grab the second Star Coin by Wall Jumping to it. After going through the Warp Pipe, Mario just needs to jump across more ice, avoiding more Spike Tops and Swoops, to make it to the Goal Pole.
Near the end of the level, the player should see a large block of ice with two Spike Tops on it, and a pipe with a Piranha Plant above it. Mario should enter the pipe to reach the Secret Exit. The Secret Exit lets Mario go through a Warp Pipe on the World Map that takes him to 5-3.