This is my attempt at a tutorial explaining how to perform unintended exits in Super Mario World. Super Mario World is a notoriously glitchy game, allowing the player to go beyond what was intended by the game designers. Normally, there is a total of 96 exits in the game. Over the years, dedicated gamers discovered several unintended exits (see https://pastebin.com/wqk0KfbM for list).
Here, I want to perform an unintended exit, the socalled 101st exit, using the Wrong Warp glitch. This route is a modification of the strat made by MrCheeze (see    • Super Mario World  Glitched 101st Ex...  ). In SMW, some rare ? blocks contain Yoshi’s wings. Grabbing those with Yoshi warps Mario to a bonus sky level. Exiting this bonus level by ‘falling’ at the bottom of the screen yields the normal exit of the level where the Yoshi’s wings were picked. The majority of levels do not contain Yoshi’s wing. However, it is possible to unintendedly spawn Yoshi’s wings by duplicating a Turn Block onto a Yoshi’s Coin. Finally, SMW has an internal counter that count how many times Mario passes through a pipe within a level. This counter has 256 possible values (from 0 to 255). Collecting Yoshi’s Wings is registered has two passes by this counter. Here is the main exploit for wrong warp exits: if the counter is at 254 and we collect Yoshi’s Wings, then the counter will get back to value 0. When this happens, the game loads a level as if Mario was coming from the Overworld. The game selects the level where to wrongly warp Mario according to the presence of Blocks at specific locations within the original level. For now, I don’t know how to find this location by myself. I just copied what have been discovered by expert gamers. Here, I believe that MrCheeze found this setup. To alter the Block layout of the level, we use extensively block duplication. warps Mario to another level. There, you can trigger an exit (normal or secret) that will be registered in the game file :). Of course, to do all this, we need infinite time. So, this is it basically.
The plan to get the 101st exit is as follow: First, get infinite time using ACE (see    • SMW ǀ Arbitrary Code Execution (ACE) ...   for tutorial). This glitch requires a bit of Powerup Incrementation to get Mario at unintended PowerUp Status 5 and pixel perfect manipulation. After, we perform some more Powerup Incrementation to get at PowerUp Status 8 to get a Key in the Reserve item box (see    • SMW ǀ Unintended Item Spawning ǀ (Win...   for tutorial). A Key is essential for duplicating some Turn Blocks. We die in a pit to reset Mario’s PowerUp Status while preserving the Item Box. Finally, we get a Feather and go to the uncleared Yoshi’s Island 1 with Yoshi. There, we go through the pipe near the checkpoint to go to the underground area and return to the main level 127 times. This will count as 254 pipe entries. Here, I use the coin counter to count how many pipe I’ve gone through. Every cycle, I eat the Piranha plant next to the pipe. After 127 cycles, I grab the Key from my Item box and kill the enemies on my way. I first duplicate the Turn block on top of the Pipe to place a Turn block at a specific position for the game to load the proper unintended level. Here, I believe this location loads the Star Warp Road #4, after the Forest Fortress. After, we duplicate some more Turn Blocks toward the end of the level to generate the Yoshi’s Wings. For this, we duplicate a Turn Block over the Dragon Coin in front of the Goalpost. The last duplication requires the Key and a Shell (see video). After the final duplication, we collect the Dragon Coin. The bottom part will now be a ?Block. This Block contains either a Key, Yoshi’s Wing, a PBalloon or a Green Shell (not used in SMW). What the Block contains depends on the Xposition of the Block, and give items in the same order. Here, the Dragon Coin ?Block contains a Key and has to be duplicated on the right side to spawn Yoshi’s Wings. After collecting the Yoshi’s Wing, we should be in the Star Road #4. This level is rendered as Forest of Illusion 1. There, we exit the level by falling into a pit. Doing this, the path for the Yellow Switch Palace is open, without activating the Palace Icon. This is registered as a new exit in the game file :)! Now, we can trigger the Yellow Switch and still have always access to the Yellow Switch Palace. Also, even though Yoshi’s Island 1 appears uncleared, we can exit the level by Start/Select. You can do this glitch on the cleared Yoshi’s Island 1 level.
Hope this video can help you in your quest to master SMW famous (and awesome) glitches.
My setup: I use an original Japanese Super Mario World cartridge played on a Super Retro Trio 3 Console (PAL version); I thus played in RealTime Attack [RTA] without Saved States. Crappy video (and sound) captured using an ‘EasyCAP’ USB adapter (SVideo signal) and ‘Honestech VHS to DVD’ software. Video editing done using Shotcut free software.


#SMW
#Glitch
#Tutorial