Mario, Luigi, Toad, and Toad are back to rescue Princess Peach once more from the clutches of the Koopa clan. However, instead of going it alone one at a time, all four can now join in thanks to the addition of drop-in/drop-out multiplayer, allowing up to four people to play through the game simultaneously. Good thing too, as this may very well one of the most difficult Mario games yet. But even with the extra help, finding all of the Star Coins and secrets scattered throughout each level of the Mushroom Kingdom is quite a challenge, which is where we come in.
Just after the checkpoint, you'll find the first coin hovering above a trio of item boxes. To grab it, grab the Propeller Suit from the item box below (or the one just beyond) and use it to spin into the coin. If playing multiplayer, you can also jump off a teammate's head.
After the checkpoint, stop at the third spinning-ground section (also the 5th one in the level) and wait for an opening to reveal itself, allowing access to a warp pipe (you may have to wait a while). Inside, you'll find the second coin between the two pipes--wall-jump or propeller into it.
You'll find the third coin just above a signpost on the higher route, after the red coin ring (also above the main course). Keep in mind that if you've taken the lower route that the coin may be too high to see--it's just before a trio of goombas. It can either be leapt to from the nearby platform or propeller hat'd into.
When you reach the first controlled tilt-platform, you'll spot a pipe in the top-right. Reach it by tilting the right side of the platform up and head inside. There, an item block reveals a "P" switch, which turns the coins into platforms and visa-versa. To reach it, hit a couple of invisible of invisible blocks to its left, and try not to grab the coins while leaping onto them. As soon as you hit the "P-Switch", use the newly formed bricks to reach the top of the room, where you'll find your coin.
After the checkpoint, you'll find a bricked-in green pipe (as well as the coin just beyond, which you can't reach). Butt-stomp through the bricks to and enter the pipe. Underground, hit the P-Switch on the right side of the room to cause the coin to drop down.
Alternate Route This level contains an alternate route that leads to the World-5 Cannon on the world map. To find it, leap from Yoshi just above the ceiling with the hidden tunnel and dash along the top to the right to find the warp pipe.
Just after the checkpoint, you'll find a coin just above the water's surface, guarded by a Cheep Cheep. Carefully skim the surface of the water to avoid being blown away by the pipe and either freeze or leap over the Cheep Cheep as he swims toward you to reach it.
To reach this coin, between the two water-spewing pipes, freeze a Cheep Cheep as he passes by below and ride the ice cube to the surface, pushing you into the coin. If you lack an Ice Flower, there's one in the box just beyond.
The final coin can be found just after the second, in a small, hard-to-reach alcove blocked by both an Urchin and a water-spewing pipe. Take out the Urchin first by freezing it repeatedly until it hits the ceiling. Now it's just a matter of getting past that darn water-spewing pipe! To do so, you're going to have to drop in on it
When you reach the three circular tracks that the blocks run along, use the propeller suit to reach a walkway above. Now hit the left-most block (by running and ducking to get beneath it) to reveal a beanstalk you can climb to a hidden area. There, you can reach the coin by riding the moving the blocks above it before dropping down.
The second coin can be found on the right side of this spinning green block, just before the first screw. Simply stand on the right edge and let it rotate you into the coin, before leaping to the nearby platform.
As you cross the series of red spinning blocks, near the end of the course, you'll spot a coin just above a Paratroopa. Either propeller into it or bounce off the Paratroopa at the height of its flight.
Just below the checkpoint is a hidden alcove containing a pipe--get into it by leaping from the left side of the spinning-ground section. After warping, simply leap to the platform on the right where you'll find the coin.
Shortly after the checkpoint, you'll reach another swing just below two shafts--the coin's in the right one. To reach it, leap toward the left wall of the right shaft as the platform swings to the right, then wall-jump into the alcove above, where the coin is.
A seemingly unreachable coin below turns reachable when the thwomp above stomps down, allowing you to drop onto it afterward. Just wait for the thwomp to drop and rise again before attempting to escape!
Just before the boss door, you'll spot a green pipe by some lava. Ride the nearby gear down to it--inside, hit the P-Switch before collecting any coins, then run along the newly formed bricks and wall-jump off the far wall to reach the coin.
Immediately before the checkpoint is a shaft of quicksand--leap into it and ride it down to a hidden, underground area. Once there, hit the P-Switch to drop down the shaft to a warp pipe. Once through, ignore the first green pipe (that's the exit) and continue onward to a yellow, upside down switch. Hit it to make some platforms appear, which will allow you to reach the coin.
Hit the left-most block here to reveal a beanstalk (to both hit the block and reach the beanstalk, leap from the nearby moving platform at its highest point). After climbing to the clouds, ride the moving platform and grab (but don't use!) the P-Switch. Hold onto it until the platform moves beneath the large coin, at which point you should use it, causing the coin to drop right onto you.
Near the end of the level, you'll find a small warp-pipe that only tiny-Mario can reach after tossing the barrels away (you can find a tiny-mushroom via the warp pipe just before, to the left of a pair of moving platforms). Hit the P-Switch after warping to reveal a path of blue coins showing where to wall-jump in order to reach the coin here.
After the checkpoint, you'll run into a fire-spitting bro (similar to a hammer brother). If you take the lower route, just left of him, you'll find a coin (it's below the walkway leading up to the fire bro).
Climb onto this platform, near the second ladder, to find three hidden blocks, one of which contains a bean stalk you can climb. Hit both the visible and invisible blocks here to reveal a path and more vines you can climb to the coin.
Try and grab a propeller hat if you're playing by yourself! Now warp down this pipe just after the checkpoint to reach an underground area. Once there, drop onto the coin and then propeller out of there. If you're playing with multiple people, one player can simply leap for it, then bubble-up afterward to escape.
The final coin requires a propeller hat to reach. It's located across from a hill near the end of the level--make a running leap from the base of the hill, then use the propeller hat shortly thereafter to reach the coin. After grabbing it, quickly wall-jump off the nearby wall to hop onto the platform above.
This lonely piranha plant is blocking a secret entrance--take him out by spitting one of Lakitu's spiny guys into him from the right, then drop down the blocks to find a secret entrance leading underground. There, have Yoshi grab the light-block (so you can see) and flutter-jump up to the coin above.
A coin can be found high above this structure that's home to numerous cactus-enemies (just before the end of the level). To reach it, highjack a Lakitu cloud from the blocks near the large piranha plant, a little ways before, then book it up and to the right to grab the coin before the cloud dissipates.
Alternate Route This level contains an alternate exit that leads to a cannon on the world map, which can blast you to World 5. Here's how to find it: Near the end of the level is a rep pipe high above that can warp you to the hidden flag pole, but it requires both the use of a Propeller Suit as well as the P-Switch a little ways before. Upon reaching the P-Switch, wait nearby for a few moments until the Pink-block on the track moves further up the track. Once it has, hit the switch, then make a mad dash toward the pipe by leaping from the pink-block to a series of newly formed blocks, just below the pipe--propeller from them (before they revert to coins!) into the pipe above to find the alternate exit.
There are two ways to get this coin. The first and easier method: As soon as the level begins, quickly either propeller suit or jump off a teammate's head (multiplayer only) to the ledge above for a coin, before it's rendered inaccessible by the moving screen. The second option is to take the middle path of the three-paths ahead--it'll lead you right to it when it loops around.
Use the penguin suit to slide through the blocks preventing access to the pipe. After warping, freeze one of the penguins on the ground level, then catch a ride on him (ducking below the low barrier) to the coin.
Enter this green pipe then bounce off the bullet bills inside to reach a coin above. Timing it can be tricky--you really only have to bounce off the first two then wall-jump from the left wall into the coin.
The second (and third) coins can only be found after activating the Red-Switch on the world-map (to the right of this world). Once you have, all of the outlined bricks from before will be filled in, allowing access to new areas. More specifically, this will allow you to enter the red pipe at the very top of the first section. After warping, ride the pink block up to the second and easily obtainable coin.
The final Star Coin is located inside the level's alternate exit. You'll find the a secret door inside the room with the rope running along the ceiling. Once on the rope, follow it so you're just above the left-most position of the first moving platform (that is, where it's positioned when it's moved all the way left). Now wait for it to move away and drop off the rope--don't worry! You'll hand in a hidden area below, containing a door. Once through, you'll find yourself in shaft with a floor that begins to lower slowly, then will drop all of a sudden. After that first sudden drop, look for the coin in a secret alcove along the right wall.