I didn't know much about this (RNG manipulation in FFXII) until recently, which is a shame, because it's a great exploit! It can be used to farm rare items in chests.
In a previous game, I spent hours to collect just a Ribbon (or maybe multiple Ribbons) from a chest. Poo. >=< This would have been nice to know back then.
Anyway, Necronopticous and I have been abusing this exploit a little in our challenge. We acquired two Zodiac Escutcheon shields from a chest
Necronopticous and I have been doing this challenge playthrough for the last few weeks, and we're nearing the end of it. I wanted to post about it as we progressed, but I didn't! I did take a few notes, though. Maybe they'll be helpful to someone in the future.
First things first: we've been following a guide on GameFAQs. Here's the link: GameFAQs: Final Fantasy XII (PS2) Low Level Challenge FAQ by JustStep25.
Secondly, the basics: 122333 are the initial levels of all