>>11792939I mean, if the objective is to get every party member to the max level, does it really matter if you do it with parties of one or parties of four? You can even get extra Exp. Eggs in the Coliseum so everyone gets double experience. I'll be honest, though, I've never actually done it. Most I've done is get upwards of level 60, and nowadays I don't even go much above level 25 to beat the game.
>>11793035An even better way is to steal Economizers from Aquila in the Coliseum. There's a specific setup with Gogo that makes it relatively easy, too, though it requires some restarting because he's not guaranteed to be carrying it, but it's much easier than finding Aquila in the Phoenix Cave or fighting Brachosaur.