PoE is actually a game, you can choose not to take the measures you decide to take, if they can be balanced so that there is no obvious choice, they have done an admirable job.

The more I think of this, the more it seems to be the bane of influence, overwhelming, mind and legend. Overleech is good, Masterful Form POE Orbs seems quite suitable, but these four are undisputed good. Amazing work with this Ascendancy IMO

Headsman (20% increase in damage done to the boss, not reflected)

Endless hunger (literally means to go to barbaric enthusiasm. Dizziness/bleeding immunity is good, but not necessary. Because of the 5s ceiling, excessive lethality is killed)
Brutal enthusiasm (ridiculous; killing otters, and permanent 50% damage, 15 international airlines and 6% damage reduction?! One node for this purpose really deserves 4 rise points)

The final advantage may be any juggling.

Overwhelming is good, but empirically, crit nodes usually look weak. The +1.5% basic crit of the foil is very good. But the basic crit of 2H weapons + 3% is exciting. More than 10% is meh to the boss. -30% of the enemies may be good, but I am not sure. Even so, it can't be more useful than Bane of Legends or Impact.

Bane of Legends is an excellent 25% (1 / 0.8 = 1.25) multiplier. Considering the fact that you can get Cull for free on sports skills, its multiplier actually Buy POE Orbs increases by 13%. 20% MS, and agriculture is a useful one. Killing the boss's 20% IAS is meh

Impact. Are you approaching me? Get 50% AoE when cleaning, and 15% damage when you face it. This may be good if you face the boss. However, when you are not next to this boss, some "Melee" skills like "Lava Strike" perform best.

Masterful Form. Duration is useless. Despite the free endurance costs, I personally think it's not worth paying for Max Frenzy (Darkray Vectors, passes) because Slayer doesn't have any way to reliably generate them in boss battles.