Brain Stem

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

   Arrival at the Summit Ledge

   When you reach the doors at the apex of High Hall, a cutscene plays showing your party escaping the Nautiloid bombardment, and your entire party is automatically gathered at the base of the Brain Stem. Catch your breath on this narrow fleshy ridge, as all active combat has ceased and fast travel remains completely locked out. Confirm your active four-person roster and designated Illithid ally are standing with you before touching anything.

2. 2

   Replenish at the Pod or Quaff Slumber

   Turn to the left of the giant Brain Stem to locate the Illithid Restoration Pod resting on the fleshy platform. If you are playing on Explorer or Balanced difficulty, interact with the pod to grant your entire party the full spell-slot and health restoration of a Long Rest. On Tactician or Honour Mode, drink your saved Potions of Angelic Slumber or Angelic Reprieve instead to refill spell slots, as the restoration pod is removed.

   Tip: Cast all long-rest buffs (such as *Aid*, *Heroes' Feast*, and *Death Ward*) before using your final recovery resources so you enter the summit at peak power.

   Watch out: On Tactician and Honour Mode, this staging area has no Restoration Pod, leaving you entirely dependent on consumables or Divine Intervention for resource recovery.

3. 3

   Final Preparation and Inventory Tuning

   Before interacting with the Brain Stem, open your party inventories to distribute scrolls, Elixirs, and high-impact consumables like Potions of Speed. Equip any specific end-game gear you have been reserving, as this platform is your final calm moment before the final sequence begins. Once you initiate the ascent, you will never be able to backtrack down to High Hall to loot fallen foes or retrieve dropped items.

   Watch out: Interacting with the stem is a hard point of no return for looting High Hall or rearranging gear across inactive companions.

4. 4

   The Decision of the Netherese Orb

   Walk up to the massive, pulsing Brain Stem and interact with it to trigger a dialogue if Gale is currently in your active party. If Gale is present and at peace with Mystra's will, he offers to climb the stem alone and detonate the Netherese Destruction Orb nestled in his chest. Choosing to let Gale ascend alone teleports your party safely down to the docks, instantly sacrifices Gale, skips both phases of the final boss battle entirely, and completes the game with full ending achievements.

   Tip: If you want to bypass the grueling final multi-stage boss combat on Honour Mode, permitting Gale to detonate his orb here safely secures the golden dice.

   Watch out: Agreeing to Gale's proposal permanently kills him and immediately ends the playthrough, barring you from playing through the final summit combat.

5. 5

   The Final Ascent

   Refuse Gale's offer—or proceed normally if he is absent or uncooperative—to commit your entire party to climbing the Brain Stem together. Watch the transition cutscene as your party scales the neural column straight up toward the Crown of Karsus. Prepare for immediate initiative rolls the moment you load into the battlefield Atop the Netherbrain.

   Tip: Ensure all concentration buffs and summons are primed right before clicking the climb prompt to maximize action economy in round one of the upcoming fight.

What you decide here and what it leads to.