Mind Flayer Colony

Walkthrough

The area in the order you play it. Tick things off as you go: they tick off in the checklists below too.

1. 1

   Enter the Colony and Free Us in the Morgue

   When you leap down the hollow tower chasm from the Moonrise Towers Rooftop, you will find yourself in the subterranean Mind Flayer Colony with fast travel disabled. Head east into the Morgue to find the butcher Chop and your former prologue companion, Us, trapped inside a suspended cage. Speak with Chop and pass a DC 14 Persuasion, DC 18 Intimidation, or DC 14 Illithid Wisdom check to obtain the key peacefully, or lockpick the cage door directly.

   Key fight: Chop
   Summon Us: Obtained by freeing the Intellect Devourer named Us from a cage inside the Morgue Don't miss

   Tip: If Chop turns hostile, focus down the Intellect Devourers first to prevent psychic burst attacks from overwhelming your party.

   Watch out: Us cannot be rescued later if you slaughter it or leave the Morgue without opening its cage, permanently locking you out of its Act 3 summoning ability.

2. 2

   Breach the Tadpoling Centre and Rescue Captives

   Move north into the Tadpoling Centre, where you will find two rows of pods holding Zevlor, allied captives, and cultists, alongside a standalone pod containing Mizora. Interact with the main console and choose "Open" to release Zevlor and your allies to battle the four newly emergent Mind Flayers and thralls. With Wyll in your party, interact with Mizora's pod console, choose "Unleash", and pass a DC 14 Persuasion check demanding a reward during the exit dialogue to secure the Infernal Rapier. Loot the brine pool in the corridor to fish out an extra specimen.

   Key fight: Tadpoling Centre (Freeing Zevlor)
   Infernal Rapier: Granted by Mizora in the Tadpoling Centre after Wyll or the player successfully persuades her for an extra reward upon release Don't missMind Flayer Parasite Specimen: Found inside a brine pool located within the Colony Don't miss

   Tip: Keep Wyll near Mizora's pod before hitting the console so the post-release cutscene immediately triggers with him in conversation range.

   Watch out: Choosing "Annihilate" on Mizora's device kills her instantly, breaking Wyll's pact and permanently condemning him to Avernus as a Lemure.

3. 3

   Clear the Barracks

   Advance into the Barracks in the western section of the colony, where Kressa Bonedaughter, her husband Maghtew Budj, hounds, and cultists bar your way. Eliminate Kressa and her entourage to pacify the barracks, noting that a Dark Urge protagonist will trigger unique past-life dialogue here. Search the fallen cult leaders to claim Kressa's weapon before pushing further into the colony.

   Key fight: Kressa Bonedaughter
   Myrkulite Scourge: Barracks: on the corpse of Kressa BonedaughterHow: defeat Kressa Bonedaughter and loot her bodyMissable because: the colony cannot be re-entered after taking the exit portal to the surface Don't miss New

   Tip: Silence or crowd-control Kressa early to prevent her from buffing the surrounding cultists and hounds with necrotic enhancements.

4. 4

   Solve the Brain Mapping Puzzle in the Necrotic Laboratory

   Turn southeast into the Necrotic Laboratory, clearing out the Death Shepherd and its legion of winged horrors and zombies. Walk over to the flesh table on the western side of the lab to collect the Resonance Stone. Next, proceed to the far southeast ledge console and solve the neural link puzzle by connecting Reason, Emotion, Memory, and Speech across non-overlapping pathways. Step into the revealed vault room to loot the Blade of Oppressed Souls, the Circlet of Mental Anguish, and the Waking Mind brain jar.

   Blade of Oppressed Souls: Inside the hidden room unlocked after completing the neural connection puzzle in the Necrotic Laboratory Don't missCirclet of Mental Anguish: Found within the secret chamber past the Necrotic Laboratory brain puzzle Don't missResonance Stone: Resting atop a table inside the Necrotic Laboratory Don't missConnecting the matching emotion, speech, memory, and reason nodes in the Necrotic Laboratory mind puzzle unlocks a secluded vault containing ancient illithid lore, the Waking Mind, and rare equipment.Braindrain Gloves: Necrotic Laboratory, southeast secret vault past the brain puzzle: on a skeleton lying next to the Blade of Oppressed Souls (X: 748, Y: -141)How: solve the Brain Mapping Puzzle and loot the skeletonMissable because: the colony cannot be re-entered after taking the exit portal to the surface Don't miss New

   Tip: When solving the puzzle, path the outer nodes along the absolute edges first (such as Emotion and Speech) so the center remains clear for Reason and Memory.

   Watch out: Carrying the Resonance Stone confers Vulnerability to Psychic damage, so stow it inside a camp backpack if you are struggling against illithid psychic blasts.

5. 5

   Consult the Slack-Skinned Head

   Take the Waking Mind back to the Mind-Archive Interface located at the desk on the west side of the Necrotic Laboratory. Insert the green jar into the console and speak with the Slack-Skinned Head that animates. Agree to consume and purge the trapped Githzerai's memories rather than leaving it trapped, which bestows a permanent psychic ward onto the character speaking.

   Inserting the Waking Mind into the Mind-Archive Interface with the Slack-Skinned Head allows you to purge the Githzerai soul, granting the party member a permanent buff called Githzerai Mind Barrier.

   Tip: Ensure the specific party member who needs the defensive boost initiates the dialogue before purging the mind.

   Watch out: Refusing the Githzerai's plea or destroying the brain jar forfeits the permanent buff entirely.

6. 6

   Replenish at the Healing Pod and Descend to the Lower Level

   Head to the northern side of the colony to locate the elevator platform leading down to the depths. Interact with the Restoration Pod standing beside the lift to fully restore all party spell slots, hit points, and ability charges just like a Long Rest. Step onto the platform and activate the Neural Apparatus to ride the lift down to the lower level.

   Tip: Re-equip your party and adjust spell preparations right after the cutscene before heading toward the descent platform.

   Watch out: Letting Gale detonate his chest blast here triggers an immediate non-standard Game Over screen and rolls the credits.

7. 7

   Witness the Chosen Three and the Netherbrain

   Approach the Flesh-Wrought Door at the bottom of the lift to trigger a story cutscene showing Enver Gortash, Orin the Red, and Ketheric Thorm controlling the Netherbrain with their three Netherstones. When the cutscene concludes, decline any party prompt for Gale to detonate his Netherese Orb unless you want an immediate premature campaign ending.

   Tip: Use all lingering high-level spell slots on pre-combat summons before clicking the Restoration Pod, as using the pod restores all expended slots.

   Watch out: Once you activate the descent elevator, you cannot return to the upper colony levels until the final boss encounter begins.

8. 8

   Slay Ketheric Thorm and the Apostle of Myrkul

   Disembark into the lowest sanctum, positioning a high-mobility companion or an invisible scout toward Dame Aylin's soul cage on the right platform. Release Aylin immediately to strip Ketheric's invulnerability while destroying the Mind Flayer and nearby Necromites before burning down Ketheric's health pool. When the skeletal Apostle of Myrkul erupts from the center pit, keep melee fighters rotated carefully out of its bone chill aura, sustain heavy radiant/bludgeoning burst damage, and loot Ketheric's unique relics from the husk upon victory.

   Key fight: Ketheric Thorm & The Apostle of Myrkul
   Reaper's Embrace: Looted from the remains of Ketheric Thorm / Apostle of Myrkul at the Colony's lowest levelKetheric's Shield: Looted from the body of Ketheric Thorm / Apostle of MyrkulKetheric's Warhammer: Dropped by Ketheric Thorm / Apostle of Myrkul after his defeat

   Tip: Cast Darkness or cast Bone Chill / use arrows of Ilmater on the Apostle to prevent it from healing by consuming surrounding Necromites.

   Watch out: Leaving the sanctum via the exit portal locks the Mind Flayer Colony permanently, instantly locking out any unlooted items or unvisited rooms.

What you decide here and what it leads to.