Seriously. Tryed to melee him, trow hellball, trow tons of different spells, go on melee, shapechange, nothing kill him. Aparently his health regen.

As you can see in this video https://www.youtube.com/watch?v=a0a1c5i39FA

I trow 2 high level spells on him, trow a hellbal and his health become higher. I have killed face Remorseless Instinct, Infinite Despair, Unrelenting Fury, and Insatiable Hunger.

This is one of the greatest problem of NWN2 IMHO. You need walkthrough to figure what you should to and some times the game simple won`t work, some times companions stop following you or stop attacking enemies. He is immortal. I don`t know if is a bug but being unable to complete the game due a mysterious bug is ridiculous. I lost half of my life`s hour trying to beat him. Watched many videos and they in this video simple spam a melee attack with a +96841654168 weapon and kill him in less than a minute, while my spells do no damage.


Purchase NWN2 was a mistake. NWN1 is a great game but this game....

What spells were you throwing? Akachi has high saves so its better to throw save denying spells like Ice strom. If you want to put Akachi into class he pretty much 30 fighter with 30 lvl wizard and cleric spells. Also he has DR

So if you want to kil lhim with casting here is few rules
1)Forget hellball. You can throw it once and he will save from it. So you only deliver 5d6 fire, frost, electric and sonic damage, which would be lowered by his DR even further
2)Cast save denying spells. Once again - forget about spells that has saves. He will succed in check and you will sit with half or zero damage
3)spam soul eater powers. All limits were removed, so eat this bustard soul as much as you want

I beat him as a controller warlock once. It was kinda hard fight, but manageable

I've reloaded my save and apparently was a bug.