In POkemon LeafGreen if you enter Mt.Moon or some place wait about 1 min. and then you should here a Pokemon noise,then if you are challenged in a WILD battle then that Pokemon is almost certain to be the Pokemon to battle,e.g. If your in Mt.Moon and you wait about a minute then you should here a Zubat Pokemon noise or Geodude Pokemon noise or a Paris Pokemon noise,then depending on wich one you heard you would be almost certain to battle that Pokemon next in a wild Pokemon battle!

P.S.Hope this helps! Bye Harleymash@yahoo.com