The Thaos fight and the condition necessary for him to transfer to a statue

[Torm51]

Last time I won we stripped of his buffs and crushed him immediately.  This is what makes Arcane Dampener or Deprive the Unworthy so OP in this fight  (Thaos buffs is the only thing that makes the fight somewhat challenging).  He never got back up and we just killed the Statues Of Woedica easily.  This time I lost my Wizard in a scripted event and forgot the Arcane Dampener ring!  So I could not strip him of buffs. (Paladin didnt take Deprive the Unworthy)  So we killed him anyway even though it took longer and we took more damage.  Anyway his soul jumps to a statue.  We kill the statues and hes back to 100% and you have to fight him again, which we did and we killed him finally.  

 

What condition has to be set for him to jump to statues and the party having to fight him again?  It did not happen last time.  Even though both times we killed him first.

 

Is it just an ability he has and I did not let him cast it last time?

 

PS

 

The game is always on the same difficulty.  Triple Crown.  So difficulties are not a variable.

Edited February 6, 2018 by Torm51

[Torm51]

answered my own question.  It is an ability he has when he gets down on endurance.  If you just interrupt him from doing it he will die and you can fight the statues without him casting the spell.  I have done that fight a lot but never noticed if it was an ability or something else.

[Boeroer]

Since I always finish off the statues first I never encountered this. I totally forgot that he can do this.