Vessel of Kulemak (Empowered)

Overview

Vessel of Kulemak is the pinnacle boss of the Abyss mechanic, fought in The Black Cathedral at level 80-82. This strategy models the empowered ending: beat the boss, steal a Lich's power three times, then return the finger and fight it at full power. The invitation costs the same either way, so the only price of the empowered route is time, and it adds Undying Hate and The Master's Reach to the unique pool. Nearly all of the profit comes from the Ancient bone that drops on every single kill, so returns are steady rather than streaky.

Setup

One Kulemak's Invitation per run, consumed when you open the encounter in The Black Cathedral. Nothing else is spent. Bring balanced resistances, because the fight deals cold, lightning, fire and physical damage, and expect to keep moving for most of it.

The Encounter

Each time you kill the boss you choose to steal a Lich's power or take the finger and end the run. For this strategy you steal three times, then return the finger on the fourth kill.

Through the first three phases the boss summons Abyssal Walkers, fires a lightning Eyebeam, sweeps the arena with a two-pass cold Cleave that comes back the other way, and channels Kulemak's Inferno, which burns everything outside a ring that tracks you until it locks in place. Engulfing Darkness covers the arena except one small circle and stops you dealing damage while you are in it, so find the circle rather than trying to fight through it. Each Lich you steal from empowers a crystal mechanic, upgrades the minions, and strengthens one of these abilities.

Phase 4 drops the crystals and the Inferno and splits the arena with a fissure. Green orbs chase you and leave desecrated ground that deals physical damage over time and blocks life and energy shield recovery, so do not stand in it. Portals on either side teleport you across the split, then go dark for a moment. Cleave and Eyebeam are always in their empowered forms here, and the boss adds a Teleport Slam.

How These Numbers Were Calculated

The drop list on the PoE2 wiki is incomplete. The page carries its own notice that the drop information needs updating, and it covers only the guaranteed ring, the Ancient bones and the unique pool. It says nothing about the currency the encounter produces, which is a real part of the income. The drops here have been filled out from other sources, including the Divine Orbs those runs returned.

The figures come from a recorded 100-run sample rather than from published drop rates. Every count is what actually dropped across those runs: 100 Ancient bones, split 36 Jawbone, 35 Rib and 29 Collarbone, and a unique pool of 59 Darkness Enthroned, 38 The Unborn Lich and 3 Undying Hate. Expenses are one invitation per run across the same 100 runs.

The guaranteed Grip of Kulemak is left out of the profit on purpose. Every kill drops one, and on this route it comes out with all four desecrated modifiers, but what those modifiers roll decides whether the ring sells for a fortune or for nothing. There is no single price to put on it, so the model ignores it. Anything you make selling rings is upside on top of these numbers, and for some players it will be the main reason to run the strategy at all.

Nearly all of the modelled profit sits in the three Ancient bones. Together they are about nine tenths of it, and one of them is guaranteed on every kill, so there is no luck involved in earning them. The risk here is price risk, not drop risk. You will get your bone every run; whether that is worth farming depends on what bones sell for that week. The invitation is also a large part of the cost, so the margin closes quickly if bone prices fall or invitation prices rise.

The rare rows are the uncertain ones. The wiki lists The Master's Reach at roughly 2 percent, and this sample recorded none, so it is not in the model at all. Undying Hate rests on three drops. A short run of kills will not match these proportions, and a hundred runs is not enough to pin down anything under a few percent.