MEX takes too much context right now; it requires knowing that Master Points come in the future, knowing that souls can use said MP to learn up to 2 new EX skills each, and that one of the new ones for the Shingen line of souls is +20 burst to all on a 6 turn cooldown. And none of us ever refer to it by something resembling its name as this stuff isn't out here yet and we don't know the official translation's gonna be.
(btw, it's 鼓舞激励, or Kobugekirei. If you plug it into an online dictionary like jisho.org, you get back 'encouragement')
MEX = Master EX skill. Nothing complicated there. You're not gonna tell me any community refers to game terms with 100% fidelity to the official terms.
Also, what context is required out of knowing you have extra EX skills available to use? You just need to know it's there, and you can use them in the future. Done. Simple.
There's still the ambiguity that each soul line gets two new ex skills. So additional context somewhere in the conversation is needed to know that it's the +20 burst gauge ex and not the +25% burst streak ex.
Are there even any other MEX worthy of even mentioning?
A quick glance and only these caught my eye:
- Shingen's completely OP BS +20 burst party buff
- Mordred's orb eater (have fun with Cthulhu+Snow Raph+Dagon+Satan or something, huehuehuehuehuehue... no actual place in anything serious probably, but fun)
- Dartagnan's Mammon-like nuke. She can't PF anyway, so a nuke mite-b-cool.
Obviously, there's only one winner MEX.
Shingen's Burst Streak can have some usage.
Herc's Overlimit Buff is also not to underestimate.
Andromeda's Defiance Buff can be of use with a taunt/cover target.
Solomon's CD Reset is incredible useful.
Joan's stackable Def buff shine's in longer battles.
Notable mention:
Arthur's MEX are both not so bad. Her Crit buff is raid wide.
Sieg's Dmg upper limit Buff can have some usage as well.
In the end, most MEX skills can be of use, just like Souls. Unless you narrow your view on only a specific Team-Composition, then of course you will only use 1, maybe 2.
Well, it's easy to say "narrow down and only view a specific thing" but... unfortunately the maths behind this game doesn't really bend that way. Is there ever a reason to use anyone except Shingen or Herc? And how can Overlimit compare to using PF on Herc?
Because it looks like Joan would be a thing for supporting (true) Ragnarok Disasters, but aside from that, are you really ever going to use anyone but one of those three?
There are plenty of reason to use other Souls then just Shingen or Herc. First of, if you dont have a team that has some decent speed, they are actually more of a burden or solo-actor when it comes to pacing.
Andromeda is even more important in True Ragnarok then Joan is (what use do you have for a random appearing dmg cut when there is no danger incoming?). Both together make the Raid inredible safe for everyone though.
Solomon becomes an incredable nuker with her reset skill, even outside of Tower. Dropping 2m+ damage in one turn can help out a lot on controlling bosses.
Hercs Overlimit makes her an incredible nuker and overall attacker in a couple turns already. With a mediocre setup I casually threw 1.8m Full Breaks around, not even mentioning her Burst damage that went to cap just like that.
Just some examples. Sure, if you have the perfect setup for a consistent 2/3 turn FB pacing, it makes sense to go for Shingen only.