I recently started playing around with pet battles..it's not amazing to me but I would definitely like to at least complete the Celestial Tournament. I have about 8 25's currently. What is the best way to fill out my roster? I need at least 15 correct? Should I just tame pets that are nearly lvl 25 and then upgrade them to rare? Leveling all my rares from 1-25 seems incredibly tedious.