World 4 (New Super Mario Bros. 2)

World 4 is the fourth normal world in New Super Mario Bros. 2. It is a snow-based world, and the levels are made up of snow or ice. The map music is the same one which was used in World 3 of New Super Mario Bros. Wii. This level is unlocked when a player completes World 3-Castle. This is also an optional world as the player can choose to go to World Flower instead.

There are 12 levels and 4 Toad Houses in this world. Of the 12 levels, 8 levels are on the main path, which includes 5 normal levels, a Ghost House, and the Fortress and Castle. Of the remaining four levels, one is the Rainbow level, one is a level requiring payment of Star Coins and the other two are secret levels. Of the 4 Toad Houses, one is red, two are green and one is yellow. The boss of this world is Morton Koopa Jr., who is fought at the castle level.

To access this level, the timer must end with the two digits '44' (that is, 'x44', where 'x' can be any number) when the player reaches the flagpole of any World 4 level. Once the level is completed, it can be accessed again by satisfying the above condition once more.

Mario begins on icy ground under several ice blocks and in front of a Cannon Pipe. Before entering the pipe, Mario can jump on the platform to get some coins. Entering the pipe shoots Mario to the sky where the Coin Heaven awaits. This level is slightly different from the earlier Rainbow levels as Mario will be walking instead of riding on a moving platform. The ground is mainly made up of various coloured pipes and also rainbow coloured platforms can be found. When Mario first touch the ground, the screen begins to autoscroll and coins drop in diagonal arrangements from the sky. Then, coins that seem to be leaping up from below, much like a jumping Cheep-Cheep, can be found. More coins then fall from above along with a 100 Gold Coin. This is followed by a Red Ring with several coin rings that move back and forth. Collecting the 8 Red Coins will earn Mario a Gold Flower in his inventory. More coins then begin to fall down to a large abyss, where Mario drops down and ends the level.

Mario begins in front of a slope where several Micro Goombas roam about. They can attach to Mario but can be shaken off by crouching. Following that, there is an ice boulder that works similarly to a Spiked Ball. They deflect upon hitting a wall or gravity pulls them down on a slope. Above that is a ? Block containing a Super Leaf. More Micro Goombas and a larger version of the ice boulder appear, followed by a rope on the ceiling to help Mario cross the area with ice boulders below. Following that is a red Koopa Troopa, followed by another ice boulder rolling up and down slopes on the ground. This is followed by the checkpoint. A ? Block containing a Super Leaf can then be found, followed by some Micro Goombas and ice boulders. Going up the structure, the player will notice to ground switching to ice and thus is slippery. Reaching the top, the player can find a Gold Ring and some Koopa Troopas where he could earn coins by sliding down the slope. At the end of the slope, an ice boulder will roll opposite, so Mario has to duck. Immediately after that is the flagpole.

Star Coins

 * Star Coin 1: The Star Coin is located in the area where Mario climbs the rope on a ceiling. There are ice boulders that continuously move about, thus obstructing the path to the Star Coin. Mario needs to get of the rope when he is above a Donut Lift at the right time, preferably on the left or right side instead of the one in the middle. Then the Star Coin is within reach.
 * Star Coin 2: Located above the checkpoint. When Mario reaches the slopy part of the level before the checkpoint, where the ground is hilly, Mario will need to jump to the second orange platform with a Koopa. He will need to bounce off the Koopa to find a higher orange platform above. Continuing towards the right will lead Mario to the Star Coin.
 * Star Coin 3: When Mario reaches the top of the structure after the checkpoint, the player can notice a ledge furthur up. Jump to that area from the incline in the ground to reach the ledge and find the Star Coin.

Mario begins in front of three moving ? Blocks. A Boo follows. Further down are two ? Blocks, one of them containing a Fire Flower. To the right is a fake door. Going up the stairs leads to the real door, taking Mario to a room where the walls are 'driven' by several Boos. Moving forward are some stairs and another fake door. There will then be several platforms on the floor which rises or lowers when Mario stands on them. This is followed by two ? Blocks, one of them containing a Super Leaf. The Boos will then 'drive' the walls in the reverse direction for a short moment. Following the ? Blocks is a Red Ring. Mario then has to climb several platforms and drop down a small shaftbefore getting crushed by the walls. Mario will then come across two ? Blocks containing coins. Following that is a P-Switch, which makes blue coins appear. After that there is a structure which Mario has to climb before getting crushed by the walls. At the top is the door leading outside. A Boo and a Springboard can be found, followed by the flagpole.

Star Coins

 * Star Coin 1: Early in the second area, there are several platforms which rises and lowers. Mario needs to stand on the last one which rises and wait till he reaches a high ledge on the left, where the Boos will then 'drive' the walls in the reverse direction. Alternatively, Mario can do a running jump from the nearby ? Blocks to reach the hidden aclove or wall kick from the right wall when the Boos begin to go backwards. The Star Coin can be found there.
 * Star Coin 2: After the Red Ring, Mario will then drop down a wall and find two ? Blocks. Mario needs to climb on these two blocks and when the blocks are about in the middle of the two walls, quickly wall jump of the walls starting with the right wall, to find the Star Coin up above.
 * Star Coin 3: Near the end of the level, Mario will find a P-Switch. Ignoring it, Mario will need to quickly climb up the structure after that and look for the Star Coin on the left wall of the structure before getting obscured by the Boo-driven wall.

Secret Exit
After the area with the platforms that rises and lowers early in the level, there are two ? Blocks, of which one of them has a Super Leaf. After the Boos reverse and return to their normal direction, climb above these blocks and when they are about to go offscreen, quickly wall kick between the two Boo-driven walls to find a secret door. Quickly enter the door and continue on to find the flagpole.

This exit unlocks World 4-B.

Mario begins in front of several Koopa Troopas and ? Blocks, one of them with a Fire Flower. A Warp Pipe with a Piranha Plant can be found, followed by more Koopas. A multi-coin Brick Block can be found here. Following this is a very tall pipe with a Piranha Plant. More Koopas can be found on a hilly area. Another tall pipe can be found, followed by more Koopas and more Piranha Plants along the way. Following that is a Coin Roulette Block. More pipes with Piranha Plants as well as Koopas can be found right after. Not far away is the checkpoint, where Mario can find a Fire Flower in one of the ? Blocks in between. More Piranhas and Koopas follow, along with more pipes. Shortly, a Gold Ring can be found. Collecting this will turn all enemies gold. In this state, if Mario uses a Koopa to attack the Piranha Plants in the pipe, the pipe will spit out coins. After a few more Koopas and Piranha Plants, the flagpole will be in reach.

Star Coins

 * Star Coin 1: This Star Coin is located high up in the air just after the first tall pipe with a Piranha Plant. To collect it, Mario will need to make a running jump from the orange platform to the right of the mentioned pipe. Alternatively, Mario can bounce off a Koopa below to reach is as well.
 * Star Coin 2: After the checkpoint, Mario needs to enter the pipe in between the two tall pipes when the Piranha Plant in it returns into the pipe. This will take Mario underground, where a single Buzzy Beetle can be found. Mario then have to use it to break the obstructing Brick Block and, if possible, quickly stop it. If so, the player should not be tempted to trigger the POW Blocks as they will break the Brick Blocks needed for Mario to reach the Star Coin. If the Buzzy Beetle isn't stopped, Mario will need to dash to the set of Brick Blocks and jump to get the Star Coin before the Buzzy Beetle triggers the nearby POW Block. Alternatively, Raccoon Mario can charge the P-Meter on one of the platforms and fly to the Star Coin instead of using the Buzzy Beetle.
 * Star Coin 3: The Star Coin is near the end of the level beside a pipe with a Piranha Plant. Mario needs to carry the Koopa on the left orange platform to the opposite platform and release it to get the Star Coin.

A payment of 5 Star Coins is required to unlock this level.

This level is full of bouncy mushroom platforms. First, Mario can see the first Star Coin (to obtain it, see below) and two Goombas that are bouncing on the mushrooms below a long orange platform. This is followed by several ? Blocks, one of which contains a Fire Flower. There are pipes which releases Goombas to the bouncy mushroom platforms. After crossing there is a Red Ring. Furthur down are some Goombas and the checkpoint. More bouncy mushroom platforms can then be found along with a single Coin Roulette Block. More Goomba-releasing pipes can be found above several mushroom platforms and orange platforms. Another long orange platform can be found. This platform is low enough to cause bouncing Goombas from Goomba releasing pipes below to reach the long orange platform. After that are several more bouncy mushroom platforms along with bouncing Goombas, and the flagpole.

Completing this level unlocks World 4-Fortress, skipping World 4-Ghost House and World 4-2.

Star Coins

 * Star Coin 1: This Star Coin can be seen immediately after Mario enters the level, under the orange platform. To obtain it, Mario needs to move further until he can find several Brick Blocks on the orange platform. Super Mario or powered-up Mario then needs to ground pound these blocks to access the bouncy mushroom platforms below. Mario then needs to go towards the left while avoiding the bouncing Goombas and being careful not to bounce too high to obtain the Star Coin.
 * Star Coin 2: After the Coin Roulette Block immediately after the checkpoint, there are some Goomba-releasing pipes above orange platforms. In between is the Star Coin. To obtain it, the player can leap from the orange platforms to the Star Coin. Otherwise, the player can bounce to the coin using a bouncing Goomba. Obtaining the Star Coin will cause a fountain of coins to be released from below.
 * Star Coin 3: When Mario reaches the long orange platform area after the checkpoint, the player can see a single ? Block next to a Brick Block. Mario needs to ground pound the ? Block to release a Mini Mushroom, which will travel towards the right and bounce on the mushroom platforms. Mario then have to travel to the end of the orange platform, where the Star Coin is, and obtain the Mini Mushroom. Mini Mario can then fit into a small gap below a Goomba-releasing pipe and jump to the Star Coin, avoiding the Goombas.

This is an autoscroll level. Mario begins on an ice platform which constantly moves up. He will first meet with a Bone Goomba. Many Bone Piranha Plants can be seen from pipes on the walls of the level. More Bone Goombas follow. A Bone Piranha Plant will then join the ride upwards. A Buzzy Beetle can then be found, followed by two Coin Roulette Blocks. Several rectangular Donut Lifts can be found. This is followed by two Bone Piranha Plants and the first Star Coin. More Donut Lifts can then be found, followed by a Buzzy Beetle. After that is the door leading to the next area, where the checkpoint and several rectangular ? Blocks can be found, one of which has a Fire Flower. The next area will feature another moving ice platform (this time moving faster), where another ? Block with a Fire Flower can be found. Two black pipes which convert fireballs into coins can be found. Exhasuting the left pipe releases three 1-Up Mushrooms while exhausting the right one releases a Star. Another Buzzy Beetle can be found, followed by more Bone Piranha Plants and a Big Bone Piranha Plant. At the top is a door to the next area. Here, two rectangular ? Blocks can be found, one with a Fire Flower, and also a Cannon Pipe. On the way up are several pipes with Bone Piranha Plants and at the very top is the boss door. Here, there will be two wheels with four rectangular ? Blocks on each wheel with two Reznors on each wheel. Mario will then have to defeat all four Reznors to complete the level.

Star Coins

 * Star Coin 1: The first Star Coin can be found easily halfway through the first room between two Bone Piranha Plants.
 * Star Coin 2: Mini Mario is required to obtain this Star Coin. Mario should already have it before entering the level. After the second Buzzy Beetle is the door to the next area. Mario should not jump up to the platform with the door as he needs to enter a mini Warp Pipe on the right wall of the lower platform and thus he won't be able to get down later, even if he uses the Donut Lifts. Entering the pipe takes Mario to a small room with the Star Coin.
 * Star Coin 3: The third Star Coin is above the Big Bone Piranha Plant in the third area. Mario will need to use the platforms to the left or right of it before the Piranha Plant blocks it.

Secret Exit
In the third room, where another ice platform can be found, Mario needs to enter a blue pipe infested with a Bone Piranha Plant which is differently coloured from the other green pipes to the left of the Big Bone Piranha Plant. To make it easier, Fire Mario can exhaust the black pipe on the right wall earlier in the level to release a Star. Entering the pipe takes Mario to a small room with coins, Donut Lifts and a green Warp Pipe on the ceiling. Entering that pipe takes Mario to the roof of the fortress, where several Donut Lifts and rectangular ones can be found, followed by the flagpole.

This exit unlocks a green Toad House and World 4-C.

The level begins with Mario on icy floor in front of a gap with a Piranha Plant. There is a Koopa Troopa above a set of blocks, with the ? Block containing a Fire Flower. Right after is a Gold Ring. Following that is an icy slope with many Goombas and Piranha Plants. After the slope there is a Red Ring which causes Red Coins to parachute down. There are also several gaps on the ground which are full of Piranha Plants. The checkpoint can then be found. Another Fire Flower can then be found in a ? Block. More Piranha Plants can be found. Maio then has to climb up several icy platforms in the air to a high ice cliff. A P-Switch can be found here, where Mario can collect blue coins by sliding down another slope, avoiding Piranha Plants and a Super Piranha Plant. Then, a ice staricase can be found, followed by the flagpole.

Star Coins

 * Star Coin 1: At the beginning of the level, the player can use the Koopa on the blocks and throw it down the slope, catching up with it until a Brick Block covering the entrance to the Star Coin is destroyed. Then Mario can run and crouch to reach the Star Coin.
 * Star Coin 2: This Star Coin is in the air just after the checkpoint and can be reached with a running jump, avoiding the Piranha Plants.
 * Star Coin 3: After the P-Switch, when sliding down the slope, the player should see a ledge somewhere above the first part of the slope, before any Piranha Plants. Mario should go up to the ledge to find the Star Coin high above which can be reached easily.

In this aerial level Mario will have to deal with many tilting mushroom platforms. Mario begins on a stationary mushroom platform which is covered in snow. The first tilting platform can be found with a ? Block above it containing a Super Leaf. Goombas and Koopa Troopas can be found, followed by a small piece of land. Going across the next tilting platform are several yellow platforms that act like balances and will drop when one side is weighed down too much. This is followed by another piece of land where more Koopas and Koopa Paratroopas can be found. Going up several tilting platforms will bring Mario to a Gold Ring where a single Koopa sits on a higher platform where Goombas can be found on the lower platforms. A ? Block with a Super Leaf can be found, along with the checkpoint on hilly ground. More tilting mushroom platforms can be found, along with a Red Ring. This follows with more balancing platforms where Mario needs to make his way upwards. More Goombas and Koopas can be found along with these platforms, which is immediately followed by the flagpole.

Star Coins

 * Star Coin 1: When Mario reaches the platform which act like balances, Mario will need to weigh down the left platform slightly to reach the higher mushroom platforms. Then, going across to the next balancing platforms, Mario needs to weigh down the platform on the right until about just before the platforms drops and jump to the left platform to find the Star Coin above.
 * Star Coin 2: Above the second piece of land (immediately after the first Star Coin), there is a Paratroopa. Mario will need to jump on it to 'remove its wings' and jump on it again to make it retreat into its shell. Then Mario should kick it towards the right and catch up with it until it falls, or carry it to a Brick Block just to the left of the piece of land with the checkpoint and activate it, which will reveal a Beanstalk to an area in the sky with the second Star Coin.
 * Star Coin 3: After the checkpoint, there are several balancing platforms. Mario needs to weigh down slightly the left platform of the first set to reach another above, then avoid weighing down another platform and jump to the highest platform to find the Star Coin which can be reached by quickly jumping off the platform.

To unlock this level the player has to locate the secret exit in World 4-Fortress.

Mario begins on land with two Fuzzies in gaps on the floor. There is a hole which Mario must drop down, taking him into a cave underground which is full of stalagmites and stalactites.. The cave is full of Fuzzies, Brick Blocks and POW Blocks, where Mario can find a Fire Flower from early in the level. After passing some more Fuzzies and stalactites, the checkpoint can be found. Following that are moving yellow platforms on tracks, where several Fuzzies also lie. More platforms can be found along with more Fuzzies and finally the exit pipe. Back in the overworld, there are several narrow cliffs between Fuzzies, and at the end is the flagpole.

Completing this level unlocks World 4-5, skipping World 4-3 and World 4-4.

Star Coins

 * Star Coin 1: Early in the level, the Star Coin can be found above some Brick Blocks with a Fuzzy. Mario should not activate the POW Blocks below as it will destroy the blocks needed to obtain the Star Coin.
 * Star Coin 2: Just after the checkpoint, there are yellow moving platforms. At the top platform, Mario must jump to a ledge on the right where a large Fuzzy can be found along with an inaccessible pipe. Mario then have to navigate past the Fuzzy to find another pipe which can be entered, taking Mario to another room full of Fuzzies and two POW Blocks. The Star Coin above the POW Blocks can be obtained by defeating the Fuzzies with the POW Blocks and then climbing up and obtaining the Star Coin.
 * Star Coin 3: Instead of entering the exit pipe, Mario must wall kick up the rightmost shaft when the Fuzzy leaves the area. The Star Coin can be found there.

Mario begins on snowy ground where, ironically, a pool of water with a Cheep-Cheep exist in front of him which the surface has not frozen in the weather. A green Warp Pipe takes Mario underwater where a Roulette Block can be found at first. Cheep Chomps are common in the level where they frequently chase after Mario. A Cheep Chomp can first be sighted just after the Roulette Block. This is followed by a blue pipe with a strong current which can push Mario furthur down the level. Many Cheep-Cheeps can also be found, some of which has trials ofcoins behind them. Another blue pipe with current can be found. Furthur down lies a Coin Roulette Block with another Cheep Chomp. Shortly after is the checkpoint. A ? Block containing a Fire Flower can be found, followed by a Red Ring and a Cheep Chomp. Continuing on is another Cheep Chomp and the second Star Coin (to obtain it, see below). Goin upwards and to the right is the last section with several more Cheep-Cheeps and a Cheep Chomp, followed by the exit pipe back to the overworld. There is a small pool of water with Cheep-Cheeps, followed by a staircase-like hill and the flagpole.

Star Coins

 * Star Coin 1: Above the second blue pipe a yellow pipe can be found on the ceiling. Entering it takes Mario back to land, where a single Cheep-Cheep can be found in the water along with four water current-producing pipes with the Star Coin just above them. To obtain it, Mario will need to perform a ground pound into the water just above the Star Coin, while avoiding the Cheep-Cheep.
 * Star Coin 2: The second Star Coin can be easily seen after the checkpoint. However, it cannot be reached normally as there are hidden blocks enclosing it. Mario will have to swim upwards the next path and instead of continuing right, swim left and navigate downwards to the Star Coin.
 * Star Coin 3: At the beginning of the last section, there is a green Warp Pipe on the floor. It takes Mario to another area with the Star Coin, two Cheep-Cheeps, water current and a ? Switch. To obtain the Star Coin, Mario needs to activate the ? Switch to turn off the current, then quickly swim to the Star Coin while avoiding the Cheep-Cheeps.

To unlock this level the player has to locate the secret exit in World 4-Ghost House.

Mario begins on snow-covered land in front of a large wall and a blue Warp Pipe, taking him underground. He will first drop onto several Ice Donut Lifts with several coins below. The floors are made of ice and thus are slippery. Amps are common in this level and many can be found following circular tracks. A ? Block with a Super Leaf can be found here, followed by a multi-coin Brick Block. More Amps follow. A lone Koopa Troopa can then be found on a platform with a single ? Block containing another Super Leaf. A Red Ring can then be found along with Ice Donut Lifts and more Amps. Immediately after is the checkpoint. A gentle ice slope can be found with several Koopas on it, followed by more Amps. Several blue pipes can be found, followed by one more set of circling Amps and the third Star Coin. This is followed by the pipe back to the overworld. In the last area of snow-covered floor, two rectangular Ice Donut Lifts can be found and finally the flagpole follows.

Completing this level unlocks World 4-Castle, skipping everything in between World 4-Ghost House and World 4-Castle.

Star Coins

 * Star Coin 1: This Star Coin can be found in the area with the third set of circling Amps early in the level. To obtain it unharmed, Mario will have to go to the hole on the other side and follow the direction of the Amps.
 * Star Coin 2: The Star Coin can be seen enclosed in an ice platform after the checkpoint. However, it cannot be reached directly. To obtain it, Mario has to backtrack until the player sees a column of Brick Blocks next to a set of three blue pipes. Mario now has to ground pound the Brick Blocks until he reaches the bottom and slide down the tunnel to underneath the Star Coin. Mario has to avoid the circling Amps to reach it.
 * Star Coin 3: The Star Coin can be easily seen below two rectangular Ice Donut Lifts located along the track of a circling Amp. Mario has to stand on one of the Donut Lifts and wait until it drops past the Star Coin. Then Mario has to quickly jump off. This requires timing due to the Amps circling the Donut Lifts.

Mario begins under a Spiked Ball enclosed in Snake Blocks. Two ? Blocks can then be found, one of them containing a Super Leaf. Snake Blocks can then be found pushing Spiked Balls around the floor. A multi-coin Brick Block can then be found very near to a Firebar. This is followed by an area with Snake Blocks on the ceiling controlling the fall of Spiked Balls, where a Dry Bones can be found. A Roulette Block follows, along with more Firebars. A P-Switch can be found below the first Star Coin, causing blue coins to appear. An area with more Snake Blocks on the ground, a single Dry Bones, a Firebar and several spiked balls can be found. This is followed by the checkpoint, where another Super Leaf can be found in a ? Block. Another area where Snake Blocks pushes the Spiked Balls on the ground can be found. More Snake Blocks can be found with a Dry Bones, where Spiked Balls occasionally drop down from the ceiling. This is followed by a Firebar and a red pipe (see Star Coin 3) below another ? Block with a Super Leaf. After that comes a fork in the path separated by Snake Blocks. The upper path has a single Giant Spiked Ball moving quickly while the bottom has two slow-moving Giant Spiked Balls. Both paths leads to the boss door.

The boss that Mario will have to defeat here is Morton Koopa Jr., taking place in a room with slanted platforms. His attacks are making Spiked Balls roll down towards Mario and also shaking the ground to stun Mario. Mario will need to stomp on him three times. He will perform his shell attack each time while spinning down the path the Spiked Balls would originally leave the room, then he will return with a large Warp Pipe on the ceiling. Defeating him will take Mario to World 5.

Star Coins

 * Star Coin 1: This Star Coin is enclosed by the ceiling somewhere before the checkpoint. There are two ways to obtain this Star Coin. One way is to use Raccoon Mario to fly to a gap (which cannot be seen) above the Star Coin and obtain it. In the absence of Raccoon Mario, Mario should not collect the preceding four coins and instead activate the P-Switch to change these coins into Brick Blocks which can be used as platforms to reach the opening to the Star Coin. In the case where the coins have been collected, a Super Leaf can be found further down near the checkpoint which is not far away.
 * Star Coin 2: The Star Coin is just after the checkpoint which is occassionally obstructed by the second giant Spiked Ball. The Star Coin can be obtained by quickly dropping to it and jumping out when the Spiked Ball is moving away.
 * Star Coin 3: When reaching the red pipe specified above which is located after the area where Spiked Balls fall from the ceiling, Mario needs to warp inside to enter another room with Snake Blocks and Spiked Balls. Mario will need to make his way up the moving Snake Blocks to reach the Star Coin.

Trivia

 * Some levels in this world have a jagged mountainous background that is similar to those found in several levels in Super Mario World.