While MissingNo. is the most famous, my favorite is the gen 1 mew glitch. Well, it's known as the "Mew Glitch," but it can be used for more than just getting Mew.
Oh yes! I’ve heard of it. Is that the Glitch you need to teleport before a trainer battle to be triggered?
My favourite Glitch is the F8 Glitch, as I like to call it. I mean, you can have a GameShark in the game through a Glitch!.And yes, the Mew Glitch is the one where you have to teleport and etc., if I remember correctly.
Mew glitch, through and through. Ever since I found out about it, I'm make sure I had a mew on my team every time I restarted my copy of Pokémon Blue. It kind of took the challenge out of the game, since Mew was ridiculously OP in those games, but still. Those are some fond memories...
Mew was most definitely overpowered but the reason for that is that you catch it when it is at level 1 which you aren’t originally supposed to find Level 1 Pokémon in the wild or encounter Mew period so... Once it is in battle and wins it will get loads of exp and it’ll instantly get to level 100
Mew and MissińgNo. glitçhes are nice, but for some reason I keep on doińg the Oldale salesman glitçh in RSE (poor man)
I think you encounter it at level 15, actually. Its legendary stats made up for the fact that it levelled up really slowly.
Berry Glitch in R/S/E. If you're lucky your game will have 100% shiny encounters due to it, I think? I heard that, at least? Cute Charm Glitch in D/P/Pl/HG/SS. Having a male Pokémon with Cute Charm lead (and having a certain TID/SID) will increase your shiny chances by 20%!
The catch anything gltich from Red and Blue, man I messed with that glitch so much as a kid since getting Safari Zone pokémon like Tauros, Scyther and Chansey was a pain before finding out you could encounter last encountered mon just outside Cinnabar if you did the gltich.