A guide to completing the World 2 Fortress in Super Mario Bros 3 for the Nintendo Entertainment System.

How to Clear the World 2 Fortress

Go to the right and stomp on the Dry Bones or ignore them. They will come back to life after a short time if you stomp them. The only way to get rid of them is to hit them if you're invincible from a Starman, or if you are wearing the Hammer Suit (a rare item).

After three Dry Bones, there is a Thwomp. When you get close to it, it will fall downward, then slowly move back up. Wait for it to start moving back up before you go past.

Then there are two more Dry Bones, and another Thwomp.

Next, there is a Boo ghost. It will stay still if you're facing it, but if you turn your back to it, it will float toward you. Make sure to turn to face it before it gets too close.

After that, there is one more Dry Bones, then a pipe. Jump and press Up to go up the pipe.

Go to the right, and carefully jump over the spikes to land on the wooden platform, but don't let the Thwomp hit you. After you go past the Thwomp and jump over the next set of spikes, there is a brick next to a wooden block, as well as a Boo. If you hit the brick, a Super Mushroom or Super Leaf comes out. If you're tall, be careful not to slide too far under that brick if you want to run and crouch to hit it. If you go too far, you'll come out on the left side and land on the spikes. You will also need to be careful not to turn your back on the Boo for too long while you do this.

Run to the right to go past the Thwomps. If you keep running, you'll go past them before they land on the ground.

At the end, you reach a door. Stand in front of it and press Up to go through.

There are several spiky platforms up ahead that move up and down. Wait for them to start moving up, then quickly run past the first two spike platforms. The next two spike platforms are longer. You can still run past them, but you might need to crouch and slide at the end if the spikes are getting too close. Or you can jump across the wooden blocks on top of these platforms, but you will also have to deal with the Boo ghosts while you jump.

After that, there is a door that goes up and down, and one small spike platform. There aren't any hidden secrets here, so just stand in front of the door while facing the Boo ghost, and when the door comes up from below, press Up to go in.

Boom Boom

Go to the right and you find the fortress boss, Boom Boom. He 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

Afterward, the fortress will be in ruins, and the locked door in the level will disappear. If you lose all of your lives and have to continue the game, the levels that you cleared will no longer be cleared, but the locked door will still be gone, so you can skip some of those levels.

Beyond where the locked door was, there is a pipe. It will take you to the pipe near World 2-3. You can also reach a Toad House next to the pipe. At this Toad House, you have a chance of getting a Super Mushroom, a Fire Flower, or a Super Leaf.

If you haven't fought the first Hammer Bro yet (this one is a Boomerang Bro), he might be reachable now. If you defeat him, you get a Music Box. If you use the Music Box on the World Map, all Hammer Bros on the map (and certain other World Map enemies in later worlds) will fall asleep until you clear a level or lose two lives.

You can now move on to World 2-3.