"The world will be destroyed. If you hold enough crystals, you may face me and form the new world."
This sounds like a job for Jake. He's a god, he's got more powers than a mortal and a couple of divine allies (Jude for example), so he should have far less issues gathering the gems. And while Gaea stated that she'd kill him when they next met, ending the world isn't likely to do him much good either. So what has he got to lose?