My gripe with him isn’t so much his fight mechanic, it’s his absolutely massive hitbox that activates whenever it moves a centimeter.
Fighting him from the air is the most efficient, I’ve discovered, but I spent a good few attempts trying to get in close with the plasma blade and would see three quarters of my HP bar disappear because my recovery animation overlapped with the startup of his charge attack that shouldn’t have been able to hit me because I was to his side or rear.
The Cataphract has been my favorite fight so far. Really challenging, but really rewarding.