So with each of the Pokemon games, you generally start with three choices of Pokemon - a Fire, Grass, or Water type. You chose that, and your rival usually chooses the most effective pokemon when compared to your choice, eg: Water against Fire.

I recall that there was a point in a version of Pokemon where you could go back and take the third Pokemon, whichever one got left over. **Am I dreaming there, or can you go and get that third Pokemon in a game? If so, which version?**