The way I beat him was first phase I did backflips and side jups to avoid, in second phase, when you lift p your sword, he dashes at you so get the lightning then backflip and he misses and while he's recovering from the miss I hit him wit it. Then I spam sliced him and used a finishing blow. If your fast enoug with the slashing you can even kill him in me finishing blow. Chances are, he will almost always dodge 1 or 2 finishing blows.
Also the jump he does for the finishing blow is pretty fucking epic. It's like a flip thingy the. A thunder strike then bam. Dead.
Also the jump he does for the finishing blow is pretty fucking epic. It's like a flip thingy the. A thunder strike then bam. Dead.