Missigno:
Everyone thinks there is not Missigno is Silver, or Gold, Thats not ture its just because they havnt even found it yet, but I have found it.
I have bribed a Nintendo tester (1-800-255-3700)
and i know how to get a Misgino. Alright
First go to Sea Foam Islands and catch a Lugia, (simple enough)and once you have cought it cloned the Lugia(learn how to on this site) oncce you have got 2 Luga's go to Fushia city, and give a moon stone to the lugia to hold.
Then save the game, then go to Sea foam islands and go to the place where you caught Lugia, another Lugia will be there(AMAZING I NEVER THOUGHT IT WOULD WORK AT FIRST) then all you have to do is catch it, once you caught it, it will immediantly evole into a Missigno because of the Moonstone.
This cheat works because i got it from the xperts try it ulself it MAY NOT WORK the first time it took me like 20 some times to do it but its worth it.
Missigno lets you have inifinte Master balls and level hundred pokemon, but it may affect some of you game sometimes when you catch it a pokemon it wont show up in the box or party(SOMETIMES)
We have more cheats and tips for this game here, Pokemon Gold cheats