Almost typed it before but it didn't send ;_; argh college internet
But really, just grind enough to where you can beat O4 then pull out all the stops (buffs, craploads of beastmasters, etc) to beat O4 one. After that, you'll gain a few hundred levels and it'll be cake. I was training off rank 20 (about level 2000 enemies) within two hours, I think.
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"Duel audio? You mean like rap battles?" - termina_rzident
KrahenProphet and Kana are on opposite ends of the Awesome Spectrum.