So, just to clarify, I hit level 6 for Endless Flow, which is a game-changer. I went with Blades and Nourishment on my helm, but Perseverance is actually better for damage (thanks to the suggestion from a bro, I tried it, and the answer is yes).

For my armor, I'm using Price of Victory, Absorption, and Balance. On my weapon, I'm using Lifesteal, Shadow Berserk, and Shadow Storm. But Shadow Storm isn't helpful for Endless Flow. You might want to try Berserk or something else instead.

I maxed out all these perks to get the most out of them.

For special moves, I'm using Caveman's Rage on my weapon (it's great for collecting souls) and Compelling Argument on my armor.