It only took me seven months, but I figured out basic comboing and beat the final boss on maximum difficulty. Absolutely recommend the game, and to be played on the highest difficulty, but I will say, when going into the final encounter, make damn sure you understand the comboing mechanics, elemental weaknesses, and status effects, make sure you have good equipment and know how to swap it out, and have useful summons for debilitation, and be ready to plan on the fly (if you intend to make it the first time) because you can't turn back. It's apparently not so hard, since 1/3 of players who beat the game beat it on Epic difficulty, but it's no joke either.

It`s pretty great. Currently on my first playthrough (I picked Epic mode)
So brutally difficult that even after 66 hours of play (I played the mobile version first so that`s why my steam playtime doesn`t match) i`m not even halfway through the game.
There`s a lot of strategy in it too.

Played EBF3 long ago when I was a kid, loved it. Now 10+ years later, this is a masterpiece. Loved every moment of it. Lots of memes, references, 4th wall breaking, and one of the best (if not the best) turn-based combat system I've ever experienced. And Phyrnna's music is so good on top of that.
The epic difficulty medals are definitely very challenging. They require a deep understanding of the game's combat system, what each character can do, what each enemy can do. It's perfect for players who love studying in-depth game mechanics.