Apostle of Myrkul — Act 2 Final Boss

Location: Top of Mind Flayer Colony (accessed after Ketheric retreats from Moonrise rooftop). No rest between phases.

Pre-Fight Checklist

Before entering the Illithid Colony at Moonrise:

Long rest — full slots, sorcery points, Channel Divinity, Superiority Dice.
Heroes’ Feast (Shadowheart L11+) — HP buff + fear immunity for all 4 party members.
Aid upcast to highest available level — +max HP party-wide.
Mage Armor on both sorcs and Bardadin (if not wearing heavy).
Elixir of Vigilance on everyone — +5 initiative.
Elixir of Bloodlust on Lae’zel and/or Karlach — extra action on kill.
Stoneskin on Lae’zel (from Shadowheart) — concentration pre-cast.
Bring 5+ Greater Healing Potions per character, 2+ Scrolls of Revivify.
Position before trigger: spread out — sorcs 12m+ from melee, Bardadin and Lae’zel up front.

Phase 1 — Ketheric Thorm (Moonrise Rooftop)

Aspect	Detail
Enemies	Ketheric Thorm + 4 necromite adds + skeletons
Gimmick	Ketheric is invulnerable until Nightsong/Aylin uses her Moonbeam on him
Strategy	Focus adds first. Kill necromites — they’ll keep spawning. Ketheric hits hard with smites but can’t die yet. Once Aylin does her thing, burst him.

Party assignments:

Bardadin (Wyll): Slashing Flourish the necromite clusters. Command: Flee on Ketheric to force OA from Lae’zel.
Lae’zel: Trip Attack → GWM nova on Ketheric once vulnerable. Use Disarming Attack to remove his weapon.
Storm Sorc: Lightning Bolt into necromite clusters. Save Chain Lightning for Phase 3.
Wild Magic Sorc: Fireball the adds. Hold Monster on Ketheric if Heightened — lands ~40%.
Astarion (if in party): Snipe necromites from range. Use special arrows.
Karlach (if in party): Enraged Throw for auto-prone on Ketheric.
Shadowheart: Bless on Lae’zel + Bardadin. Save Spirit Guardians and big heals for Phase 3.

Dialogue: Persuasion checks can skip Phase 1 entirely. DC 21 (Persuasion) to make Ketheric surrender → skip straight to Myrkul. Worth attempting — if it fails, you fight Phase 1 anyway.

Phase 2 — Descent to Colony

Ketheric teleports into the Mind Flayer Colony core. You descend via elevator. On the way:

Mind flayers + intellect devourers. Kill them methodically.
Restoration pods — USE THEM. They function as a Long Rest (full restore) once each. There are 2 pods. Use 1 before the Ketheric fight (optional dialogue skip), save 1 for AFTER Phase 3 prep if you took damage in the descent.
Save Nightsong/Aylin if you encounter her — she joins Phase 3.

⚠️ In Honour Mode, Restoration Pods are limited to one use per pod. Don’t waste both.

Phase 3 — Apostle of Myrkul ⚫⚫

This is the real fight. Ketheric transforms into the Avatar of Myrkul.

Boss Mechanics

Mechanic	Detail
HP	~350 on Honour Mode
Immunities	Necrotic, Poison. Resistant to non-magical B/P/S.
Call of the Damned	AoE pull — drags everyone toward the avatar. STR save.
Consume the Faithful	Legendary Action: consumes a nearby Necromite to heal 30-50 HP.
Scythe attacks	Melee attacks within 3m deal massive Necrotic.
Legendary Action: Gaze of Myrkul	Frighten in cone, WIS save.
Necromite spawning	Spawns Fulminating Necromites every round. They explode on death (AoE Necrotic).

Kill Order & Tactics

Kill necromites FIRST every round. Each Necromite that reaches the avatar = free heal. Focus all ranged damage on them before they reach the platform center. If a necromite is about to be consumed, kill it at range. Note: they explode on death dealing AoE Necrotic — don’t stand adjacent.
Don’t melee the avatar unless you must. His scythe + legendary actions melt anyone in melee range. Lae’zel can go in with GWM if she has Disintegrating Night Walkers (Freedom of Movement prevents Call of the Damned pull), Stoneskin active, and Helldusk/Adamantine armour.
Nightsong/Aylin is your extra DPS. If you freed her in the Shadowfell, she fights with you and is immune to Myrkul’s damage. Let her tank some hits.
Attack the avatar from range. Sorcs blast from 12m+. Throwzerker throws from 18m. Gloomstalker snipes.
Healing/Mass Healing Word as needed. Shadowheart stays back and heals.

Party Assignments

Build	Role
Storm Sorc	Wet the avatar (Create Water) → Lightning Bolt / Chain Lightning. Stay at max range. Counterspell Call of the Damned if possible.
Wild Magic Sorc	Fireball necromite spawns. Hold Monster on avatar (Heightened) — if it lands, melee auto-crits.
Shadowheart	Bless → Spirit Guardians (walk over necromites to kill them passively). Mass Healing Word on emergency. Preserve Life Channel Divinity triage.
Bardadin (Wyll)	Slashing Flourish necromites. Command: Grovel on avatar (no concentration). Hold Person works on Ketheric but NOT Myrkul (undead).
Lae’zel	Trip Attack necromites, GWM nova on avatar only when safe (after necromites are dead). Action Surge burst.
Astarion	Snipe necromites. Arrow of Undead Slaying if available. Sneak Attack on avatar.
Karlach	Enraged Throw auto-prones necromites. Returning Pike/Nyrulna from range.

Honour Mode Specifics

REST BEFORE YOU ENTER. Once you take the elevator into the Colony, you cannot leave until Myrkul is dead. No camp, no vendors, no respec.
Restoration Pods are precious. Plan to use exactly one before Phase 3. Don’t use both on the descent.
No reload. If 2+ party members drop, consider escaping — the Colony elevator works during combat (but you’d have to redo Phase 1/2).
Necromite explosion damage is real. Each one explodes for 4d8 Necrotic in a small AoE. In Honour Mode, this can one-shot squishies. Kill them from range.
Call of the Damned + melee = TPK. The pull + scythe combo can kill Lae’zel in one round if she’s pulled into melee range. Keep melee characters on the platform edges.
Save your biggest spells. You won’t get them back. Twin Chain Lightning on the avatar. Disintegrate from Wild Magic Sorc. Action Surge from Lae’zel. Use ALL resources — there’s nothing after this fight.

Post-Fight

Loot Ketheric’s body for the Netherstone and his gear.
The colony collapses — cutscene into Act 3.
If Nightsong/Aylin survived the Shadowfell, she is now a permanent ally for “Gather Your Allies” in Act 3.