Gaming

Pokémon gen 1 games. There were issues with the way data was stored. I am not double-checking any of these and writing them down from pure memory, so maybe double check the specifics before you try one.

Infinite items: (I want to say 4th slot) if you talked to the guy who teaches you how to catch pokemon and then fly to Cinabar Island and surf in the water along the east edge until you see a missingno.

Duplicate pokemon: transfer a pokemon to PC and then save the game, except when it says saving don't power off, power off. (Also works in 2nd Gen and if that poemon is holding an item it will also duplicate) but it can corrupt your game sometimes so if the pokemon comes out with ???? For stats release it and you'll be good, try again.

Get Mew: Don't talk to one specific person on the path above Misty's gym. Remember that one side tunnel where when you leave and that dude approaches you immediately? Avoid that until you get HM fly. Then go do that, but press start when he sees you and fly away to Lavender Town. The start menu opens on its own but just exit the menu. Walk due west and a lvl 5 Mew appears.

Get any pokemon: I don't remember this one, but it's something with naming your starter with the numerical code of the target pokemon and going to the East side of Cinabar Island. There was also a way to make it work with the last pokemon you saw.