After just over an hour of soloing this thing as 75 MNK/DNC I can confirm a few things about this.
1. It does run out of MP. Took ~50 mins for me.
2. It has some kind of rage mode. I had no trouble staying alive until ~60 minutes into the fight. Then it started hitting harder and more often. By this point it was no longer casting spells and getting low on HP so I was trying to keep my HP high in case of Final Sting. All my TP going into Drain Samba II and Curing Waltz II could not keep up with its increased damage output. I was wearing Rasetsu legs, hands and feet, Arakan Samue, Feral Mask, Retaliators, and DD gear in other slots. I ended up taking my Spike Earrings off to raise up evasion.
3. It's final sting hit me for 1323 and killed me. All it dropped was a Wind Crystal, but I was able to obtain it while dead.
My advice is to either come as a job that can silence it or bring a friend that can. If you want to do it like me though, I'd suggest using any damage dealing 2hrs as soon as you notice it not casting anymore. You don't want it getting into rage mode.