A guide to completing the first World 4 Fortress in Super Mario Bros 3 for the Nintendo Entertainment System.

How to Clear World 4's First Fortress

Go to the right and you will see two candles on the wall. The flames are actually enemies known as Hot Foots. If you turn your back on a Hot Foot, it will start following you. It's similar to a Boo Ghost, but it walks on the ground instead of floating in the air. Turn to face them as needed to keep them from hitting you.

Up ahead, there is a Thwomp that moves horizontally. It won't start moving until you're in line with it and you get close. Go down through the gap when it's safe.

Next, there is another Hot Foot, and a horizontal Thwomp. Without getting too close to the Thwomp, jump up to make it move, then when it's slowly moving back to its starting point, jump up to get on the ledge above it.

There is a Hot Foot up here, and another one on the right, above some pipes. You can go down the middle pipe if you want some coins and a Fire Flower. The area under the pipe has two Dry Bones, then several ? Blocks. The second ? Block from the right contains a Super Mushroom or Fire Flower, and the rest contain one coin each. There is a Boo Ghost after the ? Blocks, and another Dry Bones. To get out of the area, stand to the right of the left wall of the vertical tunnel and jump straight up to reveal a hidden block that contains one coin. Then jump on that block and stand on the right edge, then jump up to reveal another hidden block. Jump on that block and go to the right, and go up the pipe to exit the hidden area. If you want a Super Leaf, you can go to the left and try to get past the horizontal Thwomp to reach the ? Block that contains a Super Mushroom or Super Leaf.

If you didn't go down the pipe, go to the right, and the horizontal Thwomp will move when you get close. When it has moved to the left far enough, jump up and run and crouch (if you're tall) to get through the narrow gap. Then try to lure the Hot Feet to the left, then jump over them and turn left to face them, and stand somewhere that will make the Thwomp come down. Run past it as soon as it starts moving back up. Jump up and hit the ? Block to get a Super Mushroom or Super Leaf, then go right to make the horizontal Thwomp move. Run past it as soon as it is out of the way, and jump up onto the pipe.

Go to the right from there, and you'll reach the fortress boss.

Boom Boom

There is a floating platform in the middle of the area where you fight. Boom Boom will move left and right, and sometimes he will crouch and slide. Whenever he crouches, his spiky shell is not safe to stomp on. Try to stomp on him when he is running around. You can also hit him with fireballs. After you stomp him the first time, he will sometimes suddenly stop, then jump high up. It can be difficult to aim your jumps correctly when he stops and jumps, so watch him closely. After you stomp on him a second time, he will very quickly run left and right, so jump carefully to avoid letting him bump into you.

After you stomp him a third time, he is defeated, and drops a Magic Ball. Collect it and you will complete the level.

After the Level

A locked door will disappear, giving you access to a Warp Pipe, but the pipe just leads back to the pipe south of the START tile, so there's no need to go there. The locked door just gives you a shortcut if you lose all your lives.

You can optionally visit the Spade House. When you're ready to move on, you can visit World 4-4 (which is almost entirely underwater, making it a good choice for the Frog Suit, if you have one).