25 years ago today, Gyarados23 on alt.games.nintendo.pokemon shared what would eventually be known as the Old Man glitch.
Missingno.'s existence was known day 1 via cheats, and over the next few months there were reports of trainers triggering its appearance by accident, never able to figure out why. But this post is the earliest known example of someone (in the west, at least) sharing how to reliably catch it.
https://groups.google.com/g/alt.games.nintendo.pokemon/c/UVfzFBPxjX0/m/psTrs4-H_3AJMissingno. thread?
