If you were to graph out the difficulty of Torrent Peak as a whole you'd get a sine wave.
The first two chain anchors can be tricky to get to because of the water wheel puzzle. The third chain's a snap. But then the master is a brute.
Basically the lower half of a Tentacruel with shell plates over its body, this boss is nothing more than a "guess-where-the-flesh-is" minigame. At least before you pull off the first plate of armour. If you miss the master flesh and reveal a tentacle or a node, then you've just added patience into the equation. Reveal a few more non-flesh areas and you've initialized the game's "dodge-while-handling-the-chain" tutorial. It's a bit too little too late, though.
However, at least in my experience, having fought all of the enemies in this tower's main room bulked up Aeron and the chain so much that a fully powered yank at the master flesh took out nearly 1/4 of the master's health bar. If it hadn't been for all the tentacles and defense-draining water orbs I'd have made squid bits of this boss in minutes. Instead Aeron died at its watery extremities before I managed to take it out.
Honestly, on reflection, this boss was once more completely new and innovative within the scope of the game itself. This game's being a continual parade of such challenges is something for which I commend the people at Ganbarion.
But, if it hadn't been for all of the stuff you need to dodge while trying to power up your chain, I never would've known about dodging while the chain is active. I'm sure this was mentioned in one of the game's early tutorials, but actually being forced to use it early on would have made it stick in my memory.
Anyway, aside from the game's generally increasing difficulty level, something else is on the rise in it. The horror factor.
Every master howls or roars once its HP reaches the halfway mark. Underneath the Torrent Peak master's howl, though you can hear a human cry of pain. A cry that sounds like it's coming from a child.
After the fight, when Aeron offered the flesh to Elena, she didn't meekly take it but pulled it from Aeron and then tore into it like a starved wolf.
Two towers remain now, and I have to say that I'm looking forward to what they have in store. Frustrations, feelings of horror/disgust, and all.