I never learned how to do one and I never really needed to use one. I mean I went through the game just fine without them though I guess they couldve made it easier. Especially in the final Alice fight. That shit was harder than the final boss fight.
I also beat the game around late lvl 50 or early 60.

Not only haven't you used a mystic arte but you haven't learned all the artes as well since you learn some after level 60. Don't worry though I think I'm the only one who has done a double mystic arte here so I think I'm special too...

You mean when Emil and Marta do the special combo at the same time?

Also I didn't use Mystics until chapter 7ish...

Well Mystic Artes were possible in my level I mean the game just didnt explain it right to me so I never bothered with them.

No Emil can use his Mystic Arte Hellfire than use his Mystic Arte Auc su Our( The special move he use twice in a row on Richter in a movie scene) right after each other.I can tell you how to do it if you want.

Mystic Artes were the best, especially Sheena's. Emil's was ok, but most the other characters had cool looking ones. Honestly, if you don't use Mystic Artes you'll just make the game easier some other way like super powerful monsters or something.

^
True. My monster were way higher levels than me. My big badass black/blue wolf monster was like level 120+. Most of them were at least 90+ Im sure they were all in the hundreds I dont remember.

I still really wish I had used one though because they do look pretty cool and well just to actually have done one. >.

Mystic Artes aren't really that pivotal in most Tales games, they're just cool looking and devestating...in the case of DotNW some of them were pretty weak compared to what they're SUPPOSE to be like. When you see the damage ratios for Ain Soph Aur you'll realize how useless it is, Devil's Hellfire is really all you need and it's more powerful after you lose the ability to use ASA.

I actually found myself even neglecting Unison Attacks by the end of the game...I'm usually so focused on comboing that I forget and have to remind myself so I might trigger the synch abilities of my monsters.

I know how to use it after about...50 hrs. XP

the best was Genis!!