some dude told me that mew, togepi, marill, phanpy, and donphan were available in the game, seeing as they were introduced early and crap
i think i spent a year looking in veridian forest for the "Pink Bubble" he told me about, that there was a secret passage some where in the trees and you use cut, and a pick bubble comes out, giving you the chance to fight Mew. BULL CRAP!
As for Marill, i spent a few months looking at the islands that you find all the ice pokemon in for days, he told me to look for a little ball with a tail, then use strength on it, he said it would fight you as a Marill. Again, BULL CRAP!
I spent probably the most time on Togepi. He told me to go to the old cinabar mantions, and look for one of those pokemon statues with it holding an egg. I prolly spent most of my time after giving up on mew and marill until g/s. Once again, BULL CRAP!
Finally, that stupid kid told me that if i searched on the outside of Cerulean Cave, adn keep on using rock smash, that one of the walls would crumble, giving me the chance of fighting either a level five Phanpy or a level fifty donphan. I HATE THAT KID!