This impressive piece of code manipulation yields an incredible effect.

As you may know, Pokemon Red and Bluewere strung together with the digital equivalent of duct tape. This rough method of programming led to a number of infamous glitches within the game which in turn led to a sub-culture of Pokemon myths and urban legends which we explored in this article.
Years later, fans are still finding creative glitches within the games. Some fans, however, have gone a step further and have proceeded to modify the game's easily exploitable code to make their own glitches. Last week, for instance, a newly created glitch emerged which allowed players to delete their opponent's save file by battling against them while using a corrupted version of the game. The glitch was referred to as a fan-made "virus" by the Pokemon community.
Now, a new Pokemon Red and Blue virus has emerged. This one, however, is a virus you might actually want to catch.
The video above explains all of the technical details, but basically, YouTuber MrCheeze has created a tampered Pokemon save file that can be transferred to other versions of Pokemon Red and Blue through the in-game trade system. Unlike the previous virus which was used for malicious purposes, this one allows anyone who receives it to gain access to an item known as 8F.
Once you have this item, you will be able to use it to essentially customize the stats and abilities of any Pokemon in your party. More remarkable than the effect, though, is the fact that anyone who contracts this "virus" can transfer it to any other player running an uncorrupted version of the game.
It's a pretty incredible creation that is, supposedly, safe to use. That said, you should always exercise some caution when manipulating an original game just in case you lose any valuable information.