World 1-4 is the fourth level of Grass Land in Super Mario Bros. 3 and its remakes Super Mario All-Stars and Super Mario Advance 4: Super Mario Bros. 3. The player is given a time limit of 300 seconds to complete it.
This is level is set at great heights. It is an auto-scrolling athletic level that features moving platforms, which will fall down upon contact. The player will also end up squished if they stand between the left edge of the screen and another obstacle, resulting in losing a life. These platforms must be utilized carefully to make it through the level. Since they fall down upon landing, there is little time to waste, therefore the player must leap from platform to platform to avoid falling into the deep abyss. The player must also be careful not to let other obstacles push them off a platform.
The only enemies encountered throughout this level are Koopa Troopas and Koopa Paratroopas. Their shells can be used to break some of the Brick Blocks, some of which contain coins, power-ups, and 1-Up Mushrooms. Once the player reaches the end, there is a pipe that leads to the final area, where the goal awaits. A single Boomerang Brother is found here, to the left of the exit pipe.