Pretty much first time I played a Pokemon game, which was Sapphire, I only knew how to use my Starter Pokemon, and had no idea how to switch it. I was using a Treecko, so I am sure you can appreciate how difficult the game was.
To put it into perspective. I had a Sceptile by the third gym, and by the time I hit the flying gym, I believe it was in the mid 50s, and I would just leaf blade everything..... That Skarmory was a very tough match.
3DS Friend Code - 4356-0021-1824
Safari Type - Bug
Pokemon - Beautifly, Combee, Heracross