Missingno can duplicate items. Here's what you do:
1.) Put the item you want to duplicate in the 6th slot of your items.
2.) Go to Viridian City and have that 1 guy show you how to catch Pokemon.
3.) Fly to Cinnabar Island and surf along the East Coast.
4.) When you see missingno, run from it, your 6th slot item will have this, an example:
Rare candyx9 x8 x7 x6 x5 x4 x3 x2 x1 x0, repeated about 7 times, then it will say Rare Candy x99. When you get down to 1, use the trick again, very useful.
"It all starts with this, a jewel containing the ultimate power." -Shadow "I still remember what I promised you, for the people of this planet. I promise you, REVENGE!" -
No one knows Shadow better than me. Or likes him more either. Go ahead, try me.