List of Super Mario World glitches

These are the glitches found in Super Mario World.

Yoshi Replaced by Chargin' Chuck
When the player is on Forest of Illusion 1, the Yoshi that is found here can become a glitchy Chargin' Chuck thing, first the player has to be Cape Mario or Luigi and kill a Chargin' Chuck with Yoshi. After that the player should go down in a pipe with the Yoshi and go back up. If the player kills the Yoshi and got back an egg, the Yoshi is replaced by Chargin' Chuck, but, his tongue can work normally if the player ends the level with it, but the game will freeze.

Fastest Way to Earn 9,999,990 Points
Bring Cape Mario to an area with at least two Wigglers (three is better); the best place is Forest of Illusion 1. Jump on the yellow Wigglers to make them angry, and float back and forth so that the angry Wigglers are red again. Keep jumping on the Wigglers, and the player will gain points as usual. After the player gets 8,000 points, they will get a 1-Up, 2-Up, and then a 3-Up. On the next bounce, the game will display strange symbols that represent five extra lives. More glitchy graphics will appear, and they will give large amounts of points in addition to numerous coins.

This glitch was fixed in the GBA version.

Glitchy Graphics from Defeated Enemies
The balls on Iggy's and Larry's platforms can be destroyed by the sliding attack, as can the Grinders (using a triangle block). This results in glitchy graphics, most likely because the developers did not intend for these enemies to be defeated. The same thing happens if Mario does a nose diving in the second level of the Bowser battle. The Big Steely will be defeated as the head of Princess Toadstool colored red.

Make Grab Blocks Last Indefinitely
If the player takes a Grab Block and go through any pipe, it will never disappear. The player can take any carryable enemy (like Round Goomba) through a pipe and it will never jump on Mario.

In the Pipe
In any level with a pipe that extends and retracts into the ground, the player should get an item that Mario can carry (Koopa Shells, P-Switches, etc.) and leave it on top of the pipe. When the pipe retracts, the item will fall with it as normal, but when the pipe extends, the item will be stuck inside the pipe. The item will "vibrate" back and forth and eventually move out of the pipe after a few seconds.

Freeze Glitch
The player must find a Fire Flower and Feather in purse (or vice versa), Yoshi and level with berries, like Yoshi's House. Now the player must drop the Fire Flower and let Cape Mario touch it and at the same time get Yoshi to eat the berry. This causes the game to freeze and as well make Mario flash from red to green like if he touched a Starman. It can also have a more helpful effect of infinitely raising the player's coins, giving the player up to 99 lives in the process. Then the player can leave the level by pausing the game and pressing Select, although this requires the player to have cleared the level before.

Falling Through the Floor
In Vanilla Dome 2, it's possible to fall through the floor via a glitch. Towards the end, the player has to take a left and go through the "secret" passage. Then the player has to get a Buzzy Beetle shell and toss it at the first two blocks. Then the player has to quickly get a running start and slide under the blocks before they harden. Once there, the player must not release the down button. Once the player is completely surrounded, if he/she press A, he/she will Spin Jump through the floor, leading to Mario's demise.

The Double-Yoshi
In the level Chocolate Island 5, if Mario/Luigi grabs the two P-Switches (read below) and bash the Yoshi block with it, the block will create two Yoshis, but only one appears. When the Yoshi falls in an abyss, the other one appears. If the player falls in an abyss and wait until Mario and Yoshi disappears while jumping, he is traveling in a invisible Yoshi.

Grabbing two objects
If two things (like P-Switches, Shells [with two shells doesn't works], Spring, etc.) are placed in same place and Mario/Luigi run (pressing Y without drop), he will catch the two things when crouch and slide to grab the objects (the cause of drop not Y button), the player will take the two things in same time.

Mario with the Sound of Spiked Roof
In Ludwig's Castle, after Mario/Luigi passes the spiked roof, if Mario spin-jumps when the roof is in the more down possible, Mario does the same sound as the spiked roof does when it hits the floor.

Renewing P-Switch
To get this glitch to work correctly, the player should be mounted on Yoshi. Yoshi should press P-Switch and eat it swiftly. When Yoshi spits, the P-Switch will be in its normal form, ready to be pressed again.

Yoshi's Pipe Elevator
In some "up-down pipes", the player should leave the Yoshi on the pipe. Whenever the pipe moves, Yoshi will move blocky.

Miscolored Pipe
In Donut Secret 1, Mario should enter in the Warp Pipe to Bonus Area. When Mario goes up, the pipes are orange, but when Mario come down, both pipes are miscolored green.

Death and win
In Forest of Illusion 3, Mario must take the Key and go to Spin Block above the Keyhole. When the time runs out, Mario will fall and put the Key in Keyhole.

Behind the Giant Gate
It's possible to get behind the Giant Gate by flying very high above the gate or undernearth it. The game actually makes further use of this glitch, as if it's an element. This glitch is the only way to get the dragon coins behind the giant gate in Star World 3.

Duplicating block
By throwing an enemy or object at a block very close to it, block can be duplicated near it, unveiling the item, leaving the original block untouched. This can be done to either side of the block, above it, or above-diagonally to either side.

Also the game differentiates certain items by the block's horizontal position in the level. For example, blue P-Switches and gray P-Switches are actually the same object, but determined by an odd/even horizontal position of the block which contains it. Thus, by duplicating a block to the side with a P-Switch inside, it will give a P-Switch of the other color.

Walk Through Floor
In some of the underground levels it's possible to walk through the floor to the exit. First the player should grab a Koopa Shell or flipped Buzzy Beetle, then moving platforms that could kill Mario should be almost closed in. Jump on it and the player will be able to walk through until they reach an area requiring a jump.

P-Switch switching
The player should take grey P-Switch and go into the pipe. Though the P-Switch will stays grey, it will act like a blue P-Switch.

Miscolored Overworld
In order to do this glitch the player should go to the end of Chocolate Island 3. Below the goal the player must jump off Yoshi so that the screen does not scroll up. After that the overworld will be in reversed colors.