Super Mario World/Glitches

Wiggler glitch
The Wiggler glitch allows you to accumulate lots of 1-ups and points and potentially max out the counter.

To perform this glitch, you must go into Forest of Illusion 1 with a cape. Go forward until the wooden platform with the three Wigglers. Now, bounce off them repeatedly. While they will turn red and get all angry, if you leave the screen and come back they will be all calm again and you can continue stomping on them. You will get points, then 1-ups, then coins and afterwards the game will glitch and you will get huge amounts of coins, 1-ups and points. If you do this long enough you will eventually reach 99 lives and a score of 9,999,990.

P-Switch Recycle
To get this glitch to work correctly, you must be riding Yoshi. Yoshi must press the P-Switch and eat it before it disappears. When Yoshi spits it out, the P-Switch will be back to normal and you are able to press it again.

Glitchy Key
To make this glitch, you must have already pressed the Red and Green ! Switches. You must have Cape Mario and a Yoshi in Star World 4. At the level's secret exit, they must make Yoshi keep the Key in his mouth and fly with Cape Mario to hit all green ! Blocks at the left. If you drops the Key, it will be an item that changes from a Yellow Beach Koopa and an upside-down Cheep-Cheep.

Orb Glitch
This glitch can be done in Yoshi's Island 1. To begin, grab a fire flower and Yoshi, then run to the end of the level with a pipe and a Rex, near the goal. Then, wait for the piranha plant to go inside its pipe, then jump on the pipe and wait for the Rex to walk around 2 blocks away from the pipe. Then, press the button to stick out Yoshi's tongue, and immediately after, push the  button to spin jump off Yoshi while throwing a fireball, then use  to move Mario to collect the generated coin while on Yoshi's tongue. If you did it correctly, you'll briefly see a Chuck on Yoshi's tongue, then a glitchy item that looks like a Beach Koopa will appear in your item reserve.

If you use the glitchy item in a level, it acts like a Magic Ball, which instantly clears the level. Try this in weird spots and you could branch this glitch into even more crazy stuff!