I tested it only once because it takes a while, but after 15 turns, I had taken precisely 951 damage. Using this formula, we can calculate the rough amount of charisma you'll need to survive long enough to make the Xth attack in this fight:ДЇirst number is the amount of turns, the second number is the amount of damage you'll take before your attack.

As ~4 hits are dealt to you during your attack animation, you can simply subtract 4*X from f(X) to get: Thus, a more accurate formula will need to give us the damage you take before your Xth attack. However, though that is the damage dealt by the end of your Xth attack for most of the fight, your final attack will be instantaneous due to a glitch(?) where no animation is played for the finishing blow in a fight. So this isn't 100% accurate, but as a result, we can model his damage output as an arithmetic series: 4*1 + 8.5*2 + 8.5*3 + 8.5*4 +. Looking at it another way, you'll take 4 1-damage hits before your first attack, and then it's just multiples of ~8.5 from then on. Assuming you attack as fast as you can, you'll take 4 hits of asphyxiation damage while you're attacking, and then he'll up the amount of damage per hit by 1, and then you'll take another 4-5 hits before you can attack again. Basically, this guy has 4000 health, and deals linearly scaling damage to you.

Soo cubus gallery