well....i saw in a spanish site that prof. oak gives you the kanto starter when you beat RED and..... to make the rival appear you must have beaten him in mt. moon and after that have been challenged by the champion and the leader clair (dragon type), defeated them in a double battle with the rival as your partner .....and then the rival will appear the mondays and wednesdays (sorry if I wrote something wrong....im mexican and I dont know how good am I writting/speaking english)