I had no idea what this was talking about and followed links to a blog post that explained the first one ("Bigfoot"): https://www.sligocki.com/2023/10/16/bb-3-3-is-hard.html
This blog post made the "cryptids" make a lot more sense to me, so I thought I'd share that post here in case others were also wondering "what the **"
Well I did learn about a new word "probviously" - very cool.
came to comments after tfa didn't explain anything, saw your comment and thought whew, clicked the link and now I'm even more confused
Scientific American, August 1984, "Computer Recreations" (p. 19) is where I first heard about busy beavers and Turing machines.