Super Mario Bros. 3/World 7

World 7 is called Pipe Maze. Just if you look at the world map, you'll see that this really holds true - it is a giant maze made of pipes that you have to find the right way through. On this map, all the pipes have been colored, and pipes with the same color connect together, which should help you to find the right way.

And just as the world map looks complicated, the levels here are very challenging. It takes very good skills to make it past some of the puzzles presented in this world, and you will need to use all your knowledge to beat some levels.

There are no Hammer Bros on this map. Instead, there are two Piranha Plants, which however are full levels unlike the Hammer Bro fights.

This map has three mushroom houses. The first one on the left offers the standard mushroom, flower, leaf choice. The two other ones, on the other hand, have a Frog Suit, Tanooki Suit and a Hammer Suit available.

Part 1

 * There's nothing really to do here, so enter the door ahead to jump in and get to part 2.

Part 2

 * This is a vertical level where you have to get from the bottom to the top. Remember that in vertical levels, you can go sideways beyond the screen boundaries to end up on the other side, so for example, running off to the left makes you reappear on the right side of the screen.
 * At the beginning, simply jump up all the pipes, and once at the top, take the rightmost pipe to get to the other side. Here, you'll have to dodge or kill the Piranha Plants to enter the pipe at the left which leads upward.
 * Once at the top, you can jump around the blocks to get to a hidden block with a 1-up mushroom inside. The required jump is very tricky, though. Then fall down, and take the left pipe to progress.
 * You can kick the Koopa shell against the left ? block on the ground for a raccoon leaf if you want. At the top you can get another hidden 1-up mushroom if you want, afterwards, climb all the way up to the Piranha Plants.
 * You can stand on the very edge of the pipe without getting hurt by the Piranha Plant, use this to your advantage. At the top, jump on the note blocks and bounce off onto the pipe when the Piranha Plant is not out (it won't come out if you're standing on top of it).
 * If you want to get some coins, go to the right so you appear on the left side, then jump to the pipe at the top to get inside the coin area. Get all the coins, then take the top pipe to appear at the top. Otherwise, just use the blocks to climb up the structure.
 * At the top, there are two green Koopa Troopas patrolling. You can use the small gaps in the ceiling to stomp on them easily (don't kick the shells as it makes it very hard to get through this area). Climb to the top, evade the red Para-Troopa, and enter the pipe to get to part 3. As Raccoon or Tanooki Mario, you can get the third hidden 1-up mushroom beforehand by flying over the red Para-Troopa.

Part 3

 * This is the ending area. Just run across and pick the goal card to finish this level.

7-2

 * The Nippers you see in this level actually walk around. This means you have to be extra careful, especially when they decide to drop down on you from a pipe.
 * The first ? block you see contains a Fire Flower, use the ice block to reach it.
 * When you see an area with a green Para-Troopa inside, drop down. Attempt to get back up and you'll notice that there are invisible note blocks forming a ceiling over the entire area. Go down the left pipe to end up in a water area, then swim to the left and take the next pipe to get back up. You can now use the note blocks to cross the area like a bridge. There's also a hidden 1-up mushroom here which you can get using the note blocks.
 * Get all the way back and take the fourth pipe from the right to go down, then take the next pipe to land in the ending area. Grab the goal card to end this level.
 * Collecting 46 coins in this level unlocks the White Mushroom House. This can only be done as Frog Mario. Enter the level with him, then go down the pipe with a Nipper standing on it to land in a water area. Swim all the way to the left and you'll see some coins and a P-Switch. First collect all the coins, then step on the P-Switch, and very quickly jump into the water and collect all the coins near the water surface. The timing is very harsh and it's extremely hard to make it in time.

7-3

 * This is a "race" of some sorts. Jump at the first block for a starman, then run across and collect the continuous starmen before your own runs out.
 * The star allows you to simply run through any enemies you encounter. Halfway through, Lakitu will join in and start throwing Spinies at you.
 * There's a P-Switch around but it's not worth it, it just makes eight coins appear. There are also some infinite Goomba generators which you can ignore because of Lakitu.
 * At the end, you can try the 1-Up trick from World 5 again, it works on this level as well.

7-4

 * If you're Raccoon or Tanooki Mario, you can fly up at the beginning to get to a secret area with two 1-up mushrooms. Afterwards, return and get into the pipe.
 * This is an autoscrolling water level. Spiny Cheep-Cheep are coming in from both sides. Fire and Hammer Mario have an advantage here since they can knock out many of the obstacles here. The first block you see happens to contain a Fire Flower.
 * After a while, the screen will scroll into a group of Jelectros. You must swim precisely to make it safely across. At the end, you must also avoid the Big Bertha swimming around here.
 * Once you're done with the field, there is another block with a Fire Flower inside. Afterwards, simply swim through the small maze to get to the pipe leading to the ending. There, collect the goal card to finish the level.

7-5

 * At the beginning, just enter the pipe to get into the level. It is a large pipe maze with several possible paths. They may lead to various rewards such as power-ups or 1-up mushrooms, presented here is the shortest path to the exit.
 * At the beginning take the right pipe, then once up get to the right pipe again. Watch for the Bob-ombs at the bottom, and run and duck to get under the brick blocks. Kick away the ice blocks, then jump up and go through the second pipe from the left.
 * Once you've arrived at the top, run over until you see a single brick block blocking the path. Go down the last pipe. Down, watch for the green Para-Troopas and do a running jump up to the next pipe. Once up, go to the right and get through the ice block structure, then enter the pipe at the right.
 * Down, go to the right and jump up to make invisible blocks appear, afterwards return to the pipe and go up again. Go to the left, and when you see the red Koopa Troopa jump again to make invisible blocks appear. Then, run further to the left, get up onto the topmost platform and run all the way to the right. Grab the hidden 1-up mushroom if you want, then go down the pipe.
 * Run across the block "bridge" and take the pipe at the right to get to the ending area. Get the goal card to end the level.

Piranha Plant 1

 * The first two pipes need a running jump to be crossed. Since they happen to have fireball shooting plants, you need to watch for the fireballs.
 * Next, you'll see two alternating groups of Munchers popping up and going back down. You must cross the area by standing on the pipes where the Munchers are inside. Slowly cross the group of pipes this way until you get to a pit.
 * This pit needs to be crossed with a jump, but there's a Piranha Plant overhead which can give you a lot of trouble. Watch its fireballs, wait until it retreats and then jump.
 * On the other side, go down the shortest pipe. Inside, open the treasure chest to get a P-Wing and to exit the level.

Part 1

 * This fortress plays much differently depending on which form of Mario you are. If you are small Mario, or if you are Raccoon or Tanooki Mario, go through the door at the right to end up in part 2.
 * Otherwise, go to the lowermost point, and jump at the fourth column of brick blocks from the left. At the top you'll reveal a P-Switch, step on it. You can either have the joy of collecting all the coins here (it's a lot!) and go through the door at the bottom to get to part 2 as well, or you can jump to the door that appeared at the left to go to part 4.

Part 2

 * This is a typical fortress room with lots of enemies... but this time, it's eerily empty. If you're small Mario, go to the right and enter the door there to get to part 3.
 * If you're Raccoon or Tanooki Mario, however, run to the left and start flying. Go through the pipe at the top to go to part 5.

Part 3

 * You can get up to the block at the left, it contains a Fire Flower. Afterwards, go through the door to end up back in part 2. If you were small Mario, go back through the left door there to return to part 1.

Part 4

 * The pipe at the bottom leads to a bonus area. The other pipe leads to part 3.

Bonus area
Even though this is technically a bonus area, it is required to complete this level if you cannot fly. Jump at the giant ? block to get a Tanooki Suit, then go through the pipe to return to part 4.

Part 5

 * Go to the right to meet Boom-Boom once again. He is no different from before. Stomp on him three times to defeat him, since you can only get here as flying Mario you cannot use either of the other options.

Part 1

 * If you have a P-Wing, you can just fly over the blue wall to skip the entire level. You only need to collect the goal card. Otherwise, enter the door to get into the level to part 2.

Part 2

 * This is another vertical level where you have to get from the bottom to the top. Start off by running to the left to appear on the right, then climbing the stairs (but watch the Koopa Troopas).
 * You'll see a lightbulb platform, but you don't actually need it. Use the donut blocks and pipes to get up to the up arrow block. Jump on it, and avoid the blocks on the way. Afterwards, don't go to the left arrow block (it's a trap), but jump to the right and get into the pipe to be taken to the top.
 * At the top, jump onto the left arrow block, then drop down onto the lightbulb block. Jump once so it moves left to avoid the ? blocks, then once you're beside them, jump again to be taken upwards. Once you've passed them jump again (there are spikes above you) so it moves to the right, and when you see a gap in the ceiling jump again to make it move up.
 * You can either use the left arrow block, or directly jump to the up arrow block. Jump from it to the right arrow block, then duck to get under the ? blocks. Once on the other side, jump onto the wooden blocks, and from there onto the lightbulb block.
 * Use it to pass the Piranha Plants, remember to stand at the very left side so you're not hurt by them. At the top, enter the pipe to be taken to the ending area, where you can take the goal card to end this level.

7-7

 * At the beginning, enter the pipe to get into the level. It is full of Munchers, and you have to use the starmen to run over them. It is similar to 7-3, except that this time, these aren't continuous starmen and you can pick them up anytime.
 * Get the first one, then start running across the Munchers. The next block is down so you need to duck to jump at it. The third block is no trouble again, but after that, you need to jump through pipes while keeping your momentum so you make it to the fourth block before your starman runs out.
 * After the fourth starman, you'll need to duck to get below a pipe. Afterwards, just run to the exit pipe to get to the ending room, where you can finally pick up the goal card.

7-8

 * Crossing the pit at the beginning can be difficult. Use the fact that the top and bottom Piranha Plants have different speeds, and jump across when they both move favorably. If you can fly, that is also an easy way to cross the pit.
 * On the other side, the leftmost ? block has a starman, which you can use to run through all the Piranha Plants and Ptooies here. You can also get a raccoon leaf if you get down and jump at the leftmost brick block.
 * When you see a Nipper standing on a platform made of brick blocks, the middle brick block has a 1-up mushroom.
 * As Raccoon or Tanooki Mario, you can fly up from here to get on top of the pipe. There, you can find a brick block with some coins in it.
 * When you see the white block, jump along the right side of the overhead pipe to reveal a pink note block. Bounce off it to appear in a coin heaven (see below).
 * When you see the Ptooie walking on top of the pipes, take the leftmost pipe to appear in a bonus area (see below).
 * At the end, you'll see a one-of-a-kind Nipper that spews fire, it only appears once in the entire game. Watch out for it, it's best to kill it from afar. If you do kill it, you can get the 1-up mushroom it guarded from the block above where it stood.

Coin Heaven

 * Simply follow the screen and collect all the coins you see. At the end, take the pipe to reappear where you entered this Coin Heaven from.

Bonus area

 * Climb up the stairs and jump at the giant ? block to get a Hammer Suit. Afterwards, go through the pipe to end up behind the bridge.

7-9

 * This area is similar to 2-1, but structured as a giant maze. You have to find the correct passage to the exit pipe to finish this level. There are lots of dead ends here to mislead you.
 * Run forward and jump on the middle note block for a Fire Flower. Get all the way up (but watch the Para-Goomba), then go to the left through the ice blocks and jump to be on top of the structure.
 * Go to the right until you come across more note blocks. Drop down, go through the left wall of ice blocks and continue until you get to the wooden blocks, then drop down and go to the right (but watch the Para-Troopa). The middle ? block at the end contains a Fire Flower.
 * If you want to go for a 1-up mushroom (make sure that you still have enough time remaining before attempting this!), drop down after the Para-Troopa and follow the path to the left. You'll end up in a room with a row of coins, in the middle there's a hidden 1-up mushroom, duck and jump to get it.
 * Otherwise, jump up and continue to the right. Climb up the wooden blocks, continue to the right through the ice blocks, go down, and at the bottom go right again. Now, jump up then drop down behind it to finally find the exit pipe, which leads to the ending area. Collect the goal card to end this level.

Part 1

 * The idea here is to jump across all the pipes to get to the end. Of course, there are Piranha Plants and Boo Diddleys scattered all across this level to make this objective hard.
 * After the third pipe, you'll see brick blocks underneath. Drop down and carefully hit the first one (don't fall into the lava) to uncover a starman. Collecting it is necessary to get past the first Thwomp, so grab it and run forward. Hammer Mario can of course just throw hammers instead to take out that Thwomp, and Tanooki Mario can use his statue form, but it is still recommended to grab the starman.
 * Near the end, you'll see a ? block with a raccoon leaf inside. Afterwards, you'll see a second Thwomp. To get past it, jump carefully near it to trigger it falling down, and when it gets back up jump onto its pipe and right onto the next pipe.
 * The pipe to the next area is guarded by two Boo Diddleys, jump past them and look their way to avoid them. Carefully drop down onto the pipe and go down to arrive in part 2.

Part 2

 * At the beginning, you'll see a Roto-Disc and a small gap where you have to duck to get past. Don't run and duck, but go towards it to notice two Dry Bones behind it. Wait until they get to you them stomp them, afterwards you can pass the gap safely.
 * There's a Thwomp behind the next gap. You can either try to get a running slide to make it through the gap and the Thwomp in one go (rather difficult), or go near to cause the Thwomp to fall down and afterwards slide past the gap.
 * At the end you'll meet Boom-Boom as usual. Stomp on him three times, feed him five fireballs or lob a single hammer at him to defeat him.

Piranha Plant 2

 * Jump onto the horizontal pipe and do a running jump to get onto the first vertical pipe. From here, you can do one large jump to clear the first Muncher area. From here, run down (you can get past the Piranha Plant overhead without getting hurt), and jump onto the next pipe.
 * You will need to use the note blocks found here to get past the second Muncher area. If you fall down you'll more than likely get hit unless you have insane reflexes. At the end you'll have to bounce off a Para-Troopa to get to the end.
 * Go down the longest pipe to get to the ending area. Open the treasure chest to get a mushroom, this will end the level.

Airship

 * After the cutscene where Mario discovers that the King has been transformed into a Piranha Plant, Mario jumps on the airship to fight the boss of this world.
 * At the beginning, there's a nut. You could use it to cross the pit but there's two rocket engines in the way. It is a far better idea to simply jump from rocket engine to rocket engine.
 * After this part, drop down if you want for a Fire Flower. Afterwards, again either use the nut or just jump across.
 * The Rocky Wrenches can be a pain. There's a nut above your head that prevents you from jumping, so you'll need to evade the wrenches in some way. After that part you can jump up and go to the left for another Fire Flower.
 * In the next part, you need to jump from platform to platform, you can use the nuts but you don't need to. At the end is the only point where you actually need to use the nuts, to jump from the bottom to the top.
 * Enter the pipe at the end to fight the last Koopa Kid, Ludwig von Koopa. He can stomp the ground like Roy to stun you, and once you are stunned, you will be killed. Stomp on him three times or feed him ten fireballs to defeat him, then get the wand to be taken to the next world.
 * At the end, you'll be in for a surprise: Bowser has taken the princess and if you want to rescue her, you're going to need to get to his castle...