New Super Mario Bros
Once you've beaten the game go to the world map it doesn't matter which world. Then press the start button to have the pause menu coming up. Now press the following buttons in the exact same order to activate the secret challenge mode.
L, R, L, R, X, X, Y, Y(these are the buttons you have to press). One the Challenge Mode is activated enter a level of your choice doesn't matter which one. You'll notice that the screen will scroll through the level so that means that you can't return if you missed some coins or something. To de-activate the challenge mode repeat the same procedure as described above.
1-UP Mushrooms can be found by hitting/smashing blocks. They give Mario an extra life.
Blue Koopa Shells:
You can win Blue Koopa Shells in Red Toad Houses. They give Mario a shell on his back, where he can dodge enemy attacks.
Coins can be found in the open or hiden within blocks. You also recieve 1 coin for each enemy you kill with fire balls. When you get 100 coins, you get an extra life.
Mummipokey is the final boss in World 2. He will hide underground and sprout back up. Before he comes back up you will see dirt being kicked up, so that is your warning. You will have a split second to move from that area. As soon as you comes up, jump on his head. Do that a couple of times and he should be dead.
Fire Flowers are usually found after you find a Super Mushroom and give you the ability to fire, fire balls at enemys. If you get hit once you go back to the "Super Mushroom" form and if you get hit twice you go back to your original form.
To get luigi hold down L+R+A when it asked to pick a file. When you start the level you will be luigi. You need to beat world 1 before you can do this cheat.
List o' Power Ups:
This is the list of power ups and what they do:
Mega Mushroom:Turns player into incredibly big size.Also helps destroy stuff.
MiniMushroom:Turns player really small to help go into tight places and glide after jumps.
KoopaShell:Gives player a shell on the back.Also makes it where the player doesn't get hurt when player goes into the shell.
FireFlower:Gives player fire powers.With this player can shoot fireballs that bounces off the ground and wall to destroy and damage some enemies.
StarMan:Gives player invincibility and lets player destroy enemies while walking through them.
Mega Mushrooms are the rarest of all mushrooms and causes Mario to grow to a huge size. Then Mario can crush obsticales, enemys and blocks. You can earn 1-UP mushrooms, depending on how much damage you do.
You can find green mini mushrooms in blocks just like Super Mushrooms. They shrink Mario, giving him the ability to walk on water, hop on enemys (but you can't hurt them), fit into tight places (including small tubes), and glide horizontilly after jumps.
You can only save after you beat a tower or castle for the first time or when you open an area by using 5 Star Coins.
Super Mushrooms are red and can be found by hitting blocks. They double your size and allow you to be hit once without dying. If you get hit you revert back to your smaller, original form.
There are three different Toad Houses you can go to: Red, Green, and Orange. In Red Toad Houses you can get a Super Mushroom, Mini Mushroom, Blue Koopa Shell, or a Fire Flower. In Green Toad Houses you can get 1-UP Mushrooms. In Orange Toad Houses you get a Mega Mushroom.
There is atleast one Tower in each level. In Towers you start at the bottom and work your way up, instead of the usual horizontal design. At the end of each tower you face Bowser Jr.
Play as Luigi in single player mode:
At the "select a file" screen, keep pressed L and R buttons and choose one of your saved game files with the A button.
Now you'll play in the game as Luigi instead of Mario!
Extra Lives at Flagpoles:
As you may know, jumping onto the flagpole at the stage's end will net you some points (up to 8000). In this game, if you somehow manage to jump high enough and land on the very top of the flagpole, you will automatically receive a 1-Up.
To save your game anywhere on the map screen, beat the final castle in World 8. When you restart, you will have a star next to your save and you'll get the "Save" option added to your menu in the map screen.