Well i had a amazing discovery with my pokemon yellow i bought a couple of years back. As some of you may know, there are like two known ways to get missingno. Who ever told you that is wrong! I found over seven other ways to get missingno! On top 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...
You start out in Cerulean City. You must not have beat the gym there and must not have battled the guy next to the nugget bridge that says,"I saw your feat from the grass!"and of course you must go and defeat the nugget bridge people. With all that said, lets get to how the cheat works! You go up route 24 and as soon as you get to the end of the nugget bridge head left. Go down until you are one step away from being directly next to the water that takes you to the Unknown Dungeon. As soon as you walk that one step press START right when you press the down button. The guy standing there will see you but instead of engaging in battle the START menu will come up. Then you will have to teleport (using an ABRA you 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 you beat him, the buttons will be able to work again. Head north and right when you reach route 24, the START menu will pop up. When you close the menu, you will go into a battle (without being in the grass! WOW!) and the pokemon you will battle is a MEW! Now here is the hardest part. Catching this pokemon is not easy. It is treated like a legendary so you have to either put it to sleep or paralyze it and knock out most of it's HP. As soon as you do that, you will have yourself a MEW!
So, this is one way to get MEW...
You start out in Cerulean City. You must not have beat the gym there and must not have battled the guy next to the nugget bridge that says,"I saw your feat from the grass!"and of course you must go and defeat the nugget bridge people. With all that said, lets get to how the cheat works! You go up route 24 and as soon as you get to the end of the nugget bridge head left. Go down until you are one step away from being directly next to the water that takes you to the Unknown Dungeon. As soon as you walk that one step press START right when you press the down button. The guy standing there will see you but instead of engaging in battle the START menu will come up. Then you will have to teleport (using an ABRA you 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 you beat him, the buttons will be able to work again. Head north and right when you reach route 24, the START menu will pop up. When you close the menu, you will go into a battle (without being in the grass! WOW!) and the pokemon you will battle is a MEW! Now here is the hardest part. Catching this pokemon is not easy. It is treated like a legendary so you have to either put it to sleep or paralyze it and knock out most of it's HP. As soon as you do that, you will have yourself a MEW!