New Super Mario Bros. 2: 6-Fort

This level features jet engines that are can be turned off temporarily if you hit them or ground pound them. Their bases are marked with exclamation points. Go up the right side of the level and shut off the engines on that side to reach the first Star Coin. Take the platforms on paths up to the midpoint, avoiding and shutting off the engines. Go through the door on the left. Watch the pattern of the engines. You'll be safe standing on the blocks. Carefully hop up to the top of the room, where the second Star Coin is. Take the platform up and shut off the engines on the way, especially the engine below the green pipe on the right, so you can go through the pipe. It leads to a room with a random coin block and the second Star Coin. Watch the pattern of the engines. When they are not firing, hop onto the top of the engines that do not fire on top. The top two engines fire on top, so be quick. The pipe at the top will take you to the boss door. There are four Reznor on a large wheel. Once defeated, the path will open to 6-4.

Coin Total: 33,302

New Super Mario Bros. 2: 5-Fort

This level has rising lava, so be quick. Bounce off the music note blocks to the grate above and go through the door. The lava will start to rise. Quickly climb up the grates with Koopas on them and reach the I-shaped grate. It will start moving past jet engines. Avoid the engines and stay to the right to avoid spikes. Once most of it is past the grates, it rotate and appear H-shaped. Quickly jump right to another grate, then jump up for the first Star Coin. Quickly return to the moving grate and go on its left side, as it will split apart and the right side will sink into the lava. There are some Red Coins to the right. The grate will stop moving below a door. Quickly jump off the grate and go through the door. This leads to the midpoint and another door. The lava is still rising. There is a mini pipe near a jet engine. It leads to a P-Switch with Silver Coins. Climb up on the grate and it will start moving. Move right to avoid the spikes, then jump off once it passes the first set of spikes. Hop up the platforms and rejoin it. Quickly move right as it separates to get the second Star Coin. There will be a stationary grate between them. Hop over to the left grate and avoid the jet engines to get the third Star Coin. The boss door is ahead. There are four Reznor on two wheels. Once you defeat them, Ludwig appears and takes Peach to the castle.

Coin Total: 27,726

New Super Mario Bros. 2: 4-Fort

This Fort has a rising floor. There will be skulled Piranha Plants in pipes in the walls, so don't slide around too much. Some Piranha Plants will be on the floor and join you as the floor rises. There are two random coin blocks on the way. Between two Piranhas is the first Star Coin. Above them is a mini pipe to the second Star Coin. Go through the door at the top. It leads to the midpoint and another door to a similar room with a rising floor. As you go up, there will be two fire pipes. The left one will give you three 1-ups. The right one will give you a Starman, so take out those Piranhas. There's a giant one ahead of you. Above it is the third Star Coin. If you go through the blue pipe on the left on the same level as the giant Piranha Plant, you'll go through another pipe to the Red Goal, which leads to 4-C. If you don't, go through the door at the top and take the pipe cannon to the boss door. This time, there are four Reznor, but on two ferris wheels. Take them out as usually, being careful when jumping to the next wheel. After you defeat them, Morton Koopa Jr. appears and takes Peach to the castle. The path opens to 4-3.

Coin Total: 49,636
I found the secret goal after beating the final boss.

New Super Mario Bros. 2: 3- Fort

The level starts out on a platform just above the water, where a Fishbone swims around. Hop in the water and go left. If the Fishbone sees you, it will swim towards you until it runs into you or something else, which will cause it to break apart. Drop slightly down the gap and swim left to an new room with moving stones. The first Star Coin is to the left over the item blocks. Go back and through the green pipe on the right. The level becomes a vertical automatic sidescroller, with you swimming to avoid Fishbones and moving stones. The second Star Coin is on the right, past two sets of stones with spikes. The stones blocking your way will move up and out of your way. There are spiked pillars in this area. The midpoint is blocked off, so you'll be safe for a while. Get a powerup and Gold Block while you're there. As you swim up, you'll see a Red Coin Ring between pipes with currents. Go through the green one for the third Star Coin. Carefully swim up, avoiding Fishbones and spiked pillars. Go through the green pipe at the top. There are a couple of item blocks to the left of the boss door. There are four Reznor this time. Just hit the blocks below them. If the floor starts disappearing before you can get them all, hop on one of the blocks one was standing on. Once you defeat them all, Wendy drops in, then takes Peach to the castle.
If you happen to be Mini Mario, there's a mini pipe below the midpoint to the right. The level automatically scrolls up past moving stones and spiked pillars. At one point, you'll stop between stones. Stones will come in from the sides, first the bottom, then top, then center, then both the top and bottom, then the center. Avoid being crushed. The stones will then close in from the bottom, but you'll eventually be able to swim up. Don't swim up too quickly, as there are stones, spike pillars, and a Fishbone directly above. Stay below the Fishbone as you won't be able to swim up before the pillars and stones close in on you. The brick blocks to the left contain 2 1-ups. The red pipe to the right opens up the path to the cannon.

Coin Total: 19,507

New Super Mario Bros. 2: 2-Fort

Time for stone slab platforming. There's a giant Dry Bones at the start. Go up, left, and duck under a ledge for the first Star Coin. You'll reach the midpoint after a while and deal with some spiked stones. Go through the door to enter a room with moving stones. Go up past the door for the second Star Coin. Go through the door. Near the boss door, wall jump up on the stones on the left side and run over the ceiling for the third Star Coin. We go through the boss door and find 4 Reznor to battle. After defeating them, Iggy comes down on a chain, like Roy, and takes Peach to the castle.

Coin Total: 12,794

New Super Mario Bros. 2: 1-Fort

Our first Fort of the game. There are some new enemies here wearing skulls. They're otherwise like other enemies. We get a Raccoon Leaf and use a snake platform to get up. There are snake platforms near many platforms. There is a hidden 1-up under the Red Coin Ring. Go to the left for the first Star Coin. Avoid being crushed by the snake platform below it. Above is the midpoint and a door. You'll find snake platforms moving into a gap to the right. Go into that gap to find a yellow pipe. It will take you outside to a snake platform staircase and the Red Goal. This opens path to World 1's cannon. If you do not go to the Red Goal, there are snake platforms over the door. They allow you to reach a red pipe on the left. There's a P-Switch in the room that makes Silver Coins appear within the snake platforms. The Silver Coins are only a distraction, however. Once you hit the P-Switch, quickly go to the platform above the snake platforms. Here, you'll find brick blocks that allow you to reach the second Star Coin. You must collect the Star Coin before the timer runs out, as it will disappear. It's a tricky one to find. Keep climbing and you'll find the third Star Coin surrounded by a snakeplatform and guarded by a skulled Piranha Plant. Approach with caution. Take the snake platform above to the boss door. This game's Mini Boss is Reznor, first seen in Super Mario World. It's standing on item blocks in a ferris-wheel configuration. All you have to door is hit the block underneath it. Do this quickly, as it will make the floor disappear. Hop on the blocks if necessary. This Fort has two. After you take out both of them, Roy will drop in from a chain, roar, and leave. He'll take Peach to the castle.

Coin Total: 2194