Well i had a amazing discovery with my pokemon yellow i bought a couple of years back. As some of toi may know, there are like two known ways to get missingno. Who ever told toi that is wrong! I found over seven other ways to get missingno! On haut, retour au début of that the MEW glitch in yellow is actually legit! It does exsist! I did it twice and got two mew's! I tried doing these glitches and all of them work!

So, this is one way to get MEW...
toi start out in Cerulean City. toi must not have beat the gym there and must not have battled the guy suivant to the nugget bridge that says,"I saw your feat from the grass!"and of course toi must go and defeat the nugget bridge people. With all that said, lets get to how the cheat works! toi go up route 24 and as soon as toi get to the end of the nugget bridge head left. Go down until toi are one step away from being directly suivant to the water that takes toi to the Unknown Dungeon. As soon as toi walk that one step press START right when toi press the down button. The guy standing there will see toi but instead of engaging in battle the START menu will come up. Then toi will have to teleport (using an ABRA toi can catch from the route connecting Cerulean and Saffron City.) Use ABRA to warp back to Cerulean. (you must have healed at the pokemon center there first.) The START and "A" button will not work. Go and battle the swimmer at the gym and after toi beat him, the buttons will be able to work again. Head north and right when toi reach route 24, the START menu will pop up. When toi close the menu, toi will go into a battle (without being in the grass! WOW!) and the pokemon toi will battle is a MEW! Now here is the hardest part. Catching this pokemon is not easy. It is treated like a legendary so toi have to either put it to sleep ou paralyze it and knock out most of it's HP. As soon as toi do that, toi will have yourself a MEW!