at a time. If you catch a new Pokémon, it must immediately replace your current one (a process called "pivoting"). Permadeath

To understand the hype, we have to break down the two components:

You can only use items you find on the ground.

To play, you must manually create the file by patching and randomizing a base ROM. There is no "official" pre-randomized download, as the challenge requires a new, unique seed for every attempt. I beat Pokemon's Hardest Challenge (Kaizo Ironmon)