MrWint
4 HN recommenders · recommended in 6 months, 2020–2025
7:45 · 598K views · Feb 5, 2017
A tool-assisted speedrun of Pokemon Yellow by MrWint that uses arbitrary code execution to push Game Boy hardware to its limits. Through crafted inputs it injects code and ends up running other programs, such as Tetris, inside the game.
HN points to it as the standard demonstration of arbitrary code execution on a Game Boy, and of glitches and bugs being turned into a working computer.
6 comments from Hacker News
One of the crazier uses of ACE in Gameboy Pokemon games exploits is this "speedrun", by MrWint: this video ([TAS] Pokémon Yellow - Arbitrary Code Execution) I've timestamped the part where the actual exploit begins, after all of thesetup. It's worth mentioning that this isn't faked or edited in any way, and it's possible to download the input data and replicate on a emulator yourself.
It mentions Pokemon Yellow, but really any code run isn't really "run in the game" more so that it uses bugs to hack together alternate instructions for the game boy to execute. Good example: this video (skip to 1:20 for craziness)
Sometimes even after you've come up with the exploit, you can create something really beautiful for the console to run afterwards. Pokemon Yellow: this video Super Mario World: [LINK]
There is an amazing video of a similar exploit in Pokémon Yellow where they basically run a bunch of different games: this video
At the end of the day, if you look at a low enough level in the stack, there are no types. In a very concrete way, types are a high-level idea, and if the high-level stops matching the low-level, then bugs crop up. See for example Tetris implemented in Pokémon Yellow via runtime code injection: this video Their compiler missed that! So I think there's good reason to switch from talking about types as "assumptions", and think of them as compile time "assertions". Something lower-level in the stack could break the high-level code, but that doesn't make the high-level code useless, just imperfect.