World D-4 is the final level of World D and all of Super Mario Bros.: The Lost Levels.
Layout[]
The player begins in a room similar to that the one at the start of 8-4. The player must hop across a pit of lava while abstain from a long Firebar, then while abstain from another Firebar at the end of the cloister, the player can discover a power-up in a Hidden Block against the wall. Hoping across a lava pit with a Podoboo hoping out and abstain from the next Firebar, the player then must spring back off of a Koopa Paratroopa and abstain from pipes with Piranha Plants, along with Cheep-Cheeps that hop out of the lava until the player arrive at the next hall. After a falling lift and a Firebar, the player will discover a Warp Pipe at the end of the hallway.
The next area is an overworld area, with the first enemy being a indict for Hammer Brother. After the second pipe with a Piranha Plant, wind will begin blowing. The player will next come into contact with two Koopa Paratroopas, two Bloobers, another Piranha Plant, and a hidden Poison Mushroom before a flight of stairs, which the wind will stop blowing beforehand. After a hop across a large pit, the player will discover a Warp Pipe with a Piranha Plant.
The third area is a easy underground chamber with coins and a Coin Block over the start of the third row of coins.
The fourth and final area has the player arrive back to the castle, where they will encounter a fake fire-breathing Bowser's Brother (or in the case of All-Stars the actual Bowser's Brother who only throws hammers). Above him is a row of ? blocks, with the fifth from the right rein in a power-up. The next Warp Pipe with the Piranha Plant and Bloobers surrounding it will take the player back to the start of the level. After the pipe is a Hammer Brother, followed by a narrow passage that the player must crouch and slide through if they are in a Super or Fire form. Using a lift to get up over a ledge, the player then has to time a fall into a narrow passage while avoiding a Podoboo. Finally, the player will be faced with a fake Bowser, who throws wheeze fire and has a Firebar over him (in All-Stars, this was replaced by the actual Bowser himself who only throws hammers). Upon win against him or touching the ax, the player will rescue Princess Peach and finished the game.
Enemies[]
| Name | Count |
|---|---|
| Piranha Plant | 10 |
 Firebar
|
5 |
| Podoboo | 2 |
| Red Koopa Paratroopa | 1 |
| Cheep-cheep | (infinitely spawned from the lava in the first area) |
| Hammer Brother | 2 |
| Green Koopa Paratroopa | 2 |
| Bloober | 5 |
| Fake Bowser's Brother (Spiny) (FDS only) | Mid-level boss |
 Bowser's Brother (SNES only)
| |
| Fake Bowser (Spiny) (FDS only) | Boss |
| Bowser (SNES only)
|