When I got Pokemon Ruby, I eventually got really close to catching everyone. Then a friend made me battle him and his Fire Red. Suddenly my Pokedex has 386 pokemon in it and I became like 200 Pokemon away instead of 10. I was so depressed. I wanted to punch that kids head off. Another bad experience was when I traded my level 75 or so Walrein to a friend in my summer camp so he could beat the Elite 4. he beat it, but then his battery died before we coud trade back. I lost one of my best pokemon.
What was my point here again? oh, yeah catching them all without cheating is possible, but it will be a long road and as soon as you succeed another 100 will come out
Also, why all the 3rd gen hate? Swampert and Sceptile were awesome, and groudon could do one turn Solarbeams all the time. There is nothing even remotely unbadass about that