World 4-5 is the seventh level of World 4. It can be unlocked by clearing World 4-.
This is an underground level with Bob-ombs and platforms that act like drawbridges. Some bricks can only be destroyed by blowing up a Bob-omb, which is needed for Mario to get past some areas. This skill is also used to get the first Star Coin. To get the second Star Coin, the player must wait until a drawbridge goes up. Next, he must hit the Bob-omb above him, destroying some blocks, allowing him to get the coin. After a few more drawbridges, the player should notice one that has a pipe with blocks covering it. If Mario blows up a Bob-omb on top of the pipe, he can enter it and, by breaking more blocks with Bob-ombs, he can get the last Star Coin. When Mario leaves the pipe, he will reach the pole.
- Star Coin 1 - To get the first Star Coin, Mario should blow up a Bob-omb near the side of a box of bricks.
- Star Coin 2 - When the drawbridge goes up, a Bob-omb can be detonated and the Star Coin can be collected.
- Star Coin 3 - A Bob-omb can be used to destroy blocks that are blocking a pipe. Inside, five Bob-ombs are available to destroy the blocks so Mario can grab the Star Coin.