I believe a better way to roll this out would have been 12 Zodiac based monsters. You fight them the same way Dhorme Chimera and Hydra are. BEFORE that, you have to go out and do FATEs with your Zenith weapon. As you do, it builds a random amount of "charges," and after, say, 200 or so charges or something like that, it will be fully charged and you can fight one of the Zodiacs. Defeat it, and you get that monster's Atma. Rinse, repeat. Still a bit timesink-ish, BUT it doesn't completely rely on BS luck and makes you put in work with the content to get the job done. I could live with that model, but this totally random garbage isn't fun or challenging. And yes, there are other weapons, but I want to progress the one I spent months earning in the first place, and don't feel playing the lottery is the best approach to doing it.