Key takeaways
- Undercity is a region, not just the Bhaal Temple The Lower City Sewers are its main connective area, while the ruins and temple occupy the northern end.
- Most routes begin in the Lower City Sewers You can enter from several manholes, prisons, cellars and faction hideouts in the Lower City.
- The Murder Tribunal is separate from the sewer network It is reached through Candulhallow’s Tombstones and is not normally entered from the sewers.
- The Undercity Ruins contain several progression gates The first stone door can be opened with the Amulet of Bhaal, by becoming an Unholy Assassin, with Knock, or by shooting the hanging corpses that operate its mechanism.
- The Bhaal Temple requires both route knowledge and quest progression Defeating Ghislev opens the approach, but the temple doors still require the Amulet of Bhaal.
- The Morphic Pool is a point of no return Entering it prevents returning to camp, changing the active party, accessing stored equipment or respecing with Withers during the endgame sequence.
About this guide
Spoiler warning: This guide covers major Act Three revelations, the Murder Tribunal, Orin the Red, the Dark Urge, the Bhaal Temple, the Morphic Pool and the route into the endgame.
Overview
The Undercity is the underground region beneath the Lower City of Baldur’s Gate in Act Three of Baldur’s Gate 3. It is not a single room or merely the area around the Bhaal Temple. In practical terms, it is a broad subterranean region made up of the Lower City Sewers, Guildhall, Abandoned Cistern, Murder Tribunal, Undercity Ruins, Ancient Lair, Bhaal Temple and Morphic Pool. Some of these areas have their own location labels and separate entrances, but they form the relevant underground network beneath the city.
The region is where Baldur’s Gate’s hidden criminal organisations, undead economies, Bhaalist cults and the remains of older buried cities overlap. It is also one of the most important progression zones in the game. The sewers support several companion and faction quests, the Murder Tribunal leads towards Orin, the Undercity Ruins provide the route to the Bhaal Temple, and the Morphic Pool is the gateway to the final sequence.
Included areas
Lower City Sewers
The Lower City Sewers are the main transport network beneath Baldur’s Gate. They cover a large part of the Undercity and provide access to the Undercity Ruins, while also linking to the Guildhall, Abandoned Cistern and routes towards other underground locations.
The sewer system is not a linear dungeon. It contains multiple loops, dead ends, ladders, locked doors, side chambers, faction encounters and quest-dependent events. Its exact naming can be confusing because the minimap may continue to show sewer-style surroundings even when the party is approaching a separately labelled area.
Guildhall
The Guildhall is the underground headquarters of the Guild, Baldur’s Gate’s principal criminal syndicate. It functions as a meeting place, black-market social centre and administrative base for local gangs and dealers. During Act Three, Nine-Fingers Keene leads the Guild while attempting to contain the growing influence of the Stone Lord and the Zhentarim.
The Guildhall is a proper subarea rather than simply another sewer room. It has its own residents, faction politics, merchants and quest outcomes. It can connect back to the sewers through more than one route, including a locked door and a hidden internal passage. One sewer-side door can be opened with Severn’s Sewer Key or a Sleight of Hand check.
Abandoned Cistern
The Abandoned Cistern is a separate sewer-adjacent location associated with the Stone Lord plot and the pursuit of Minsc. It should not be collapsed into the ordinary Lower City Sewers when describing the Undercity’s layout.
Murder Tribunal
The Murder Tribunal is a hidden Bhaalist institution reached through Candulhallow’s Tombstones, a funeral business in an alley near the city graveyard and behind the Elfsong Tavern. It is not connected to the sewer network in the normal way.
The tribunal is presided over by Sarevok Anchev and contains the ghosts of notorious Bhaalspawn. Its central purpose is to test candidates for the title of Unholy Assassin. It is also the most direct route to obtaining the Amulet of Bhaal, which is needed to pass the Bhaal Temple’s final entrance.
Undercity Ruins
The Undercity Ruins are the northernmost part of the region. They are the remains of an older subterranean city, with broken houses, ruined masonry, cliffs and passages that descend towards Bhaal’s territory.
The location begins after travelling north from the sewers through a stone archway. The Undercity Ruins waypoint is near the entrance. The area then divides into several meaningful sections, including the Ancient Lair, Manslaughter Chasm, the approach to the Bhaal Temple and the route to the Morphic Pool.
Ancient Lair
The Ancient Lair is a secluded crypt and workshop belonging to Mystic Carrion, the mummy lord connected to Free the Artist. It is reached through a passage west of the Undercity Ruins waypoint.
The lair contains treasure, undead guardians and the Spell Rot curse. Spell Rot damages affected spellcasters when they cast spells, making the area particularly dangerous for parties that rely heavily on repeated magic. Exploring the lair is important for resolving Mystic Carrion’s storyline and for finding information and objects connected with Thrumbo.
Bhaal Temple
The Bhaal Temple is the innermost sanctuary of the Cult of Bhaal. It occupies the northeastern part of the Undercity Ruins and can only be reached by coming through the sewers and then crossing the ruins.
Its principal spaces include the trapped bridge, the outer perch, the central altar and the Chosen’s Room. The temple is the setting for the confrontation with Orin the Red and for major Dark Urge decisions.
Morphic Pool
The Morphic Pool is the northernmost section of the Undercity and the launch point for the game’s final sequence. The party reaches it from the Undercity Ruins, travelling beyond the Bhaalist area to a dock where a skiff crosses to the pool.
The transition is not a normal area change. It is a major progression commitment, so finish desired Lower City and companion business before boarding the skiff.
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Entering the Lower City Sewers
The sewers have numerous entrances. The most useful are:
The easiest general-purpose entrance is the manhole near Basilisk Gate. The Heapside Prison route is also useful if you are already investigating the city watch or exploring the barracks.
Entering the Lower City Sewers
| Name | Details |
|---|---|
| Basilisk Gate Barracks and Heapside Prison | descend through the prison’s pit latrine. |
| Knights of the Shield Hideout | use the hatch in the hideout. |
| Street manhole near Stormshore Tabernacle and Basilisk Gate Barracks: a direct surface entrance. | — |
| Elfsong Tavern | enter through the Knights of the Shield Hideout in the cellar. |
| Flymm Cargo | use the basement route. |
| Lady Jannath’s Estate | pass through the Abandoned Cistern route. |
| Szarr Palace | enter through Cazador’s Dungeon after opening the relevant route from inside. |
Reaching the Undercity Ruins
From the sewer network, travel north until the surroundings open into a ruined cavern. The location name changes to Undercity Ruins near the stone archway at approximately X: -138, Y: 907, and the waypoint becomes available.
The first major obstruction is the magical stone door. It cannot be lockpicked. Verified ways to open it include:
The corpse mechanism is particularly useful if you have not completed the Murder Tribunal. It also allows a party to explore the ruins without committing to Sarevok’s route.
Reaching the Undercity Ruins: steps
- 01Use a ranged attack on either of the hanging corpses above the mechanism.
- 02Show the Amulet of Bhaal.
- 03Become an Unholy Assassin of Bhaal during Impress the Murder Tribunal, then use the amulet.
- 04Cast Knock on the door.
Reaching the Bhaal Temple
Once beyond the first door, cross the ruins and deal with Farslayer of Bhaal Ghislev. During this encounter, the Bhaalists attempt to complete a ritual while the party crosses the cavern and bridge.
The approach is dangerous because the bridge contains Marble Plates and Sanguine Vents. These traps can trigger unstable blood effects, and candles along the bridge may ignite surfaces. The traps require Perception checks to identify.
Defeating Ghislev removes the lock on the temple entrance, but the doors still require the Amulet of Bhaal. The amulet is normally obtained through the Murder Tribunal, although quest and progression states can affect how the route is presented.
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For a thorough but practical run, use this order:
This route is not mandatory, but it avoids repeatedly retracing the sewer network and reduces the risk of reaching the endgame before finishing side quests.
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The Undercity has a very large character population spread across its subareas. The following directory groups the most relevant named figures by role and location. It does not treat every unnamed Bhaalist, guard, cultist or sewer creature as a resident.
Reaching the Bhaal Temple: steps
- 01Enter through the Basilisk Gate or another convenient sewer entrance.
- 02Activate the Lower City Sewers waypoint and map the nearby loops.
- 03Investigate sewer quest encounters connected with Orin, Minsc, the Guild and the Stone Lord.
- 04Visit the Guildhall if you are resolving the Guild, Zhentarim or Stone Lord storyline.
- 05Explore the Abandoned Cistern if your current quest points towards Minsc.
- 06Travel north to the Undercity Ruins and activate its waypoint.
- 07Speak with Voiceless Penitent Bareki and investigate the nearby passage to the Ancient Lair.
- 08Collect Sarin’s Skull before moving on if you are completing the Sarin encounter.
- 09Enter the ruins through the corpse-operated stone door if you have not yet completed the Murder Tribunal.
- 10Search the Manslaughter Chasm area before defeating Ghislev if you want the Bonespike Gloves from Strangler Luke.
- 11Complete or bypass the Murder Tribunal and obtain the Amulet of Bhaal.
- 12Cross the Bhaalist approach and enter the temple.
- 13Resolve Orin’s confrontation and any Dark Urge decisions.
- 14Only then proceed towards the Morphic Pool, after completing remaining city objectives.
Major residents and story figures
Lower City Sewers and sewer-linked areas
Orin can appear in the sewers as part of Rescue Orin’s Victim if her kidnapping event has not already been triggered by a long rest. One documented trigger occurs near the Knights of the Shield Hideout entrance, while another occurs close to the Undercity Ruins waypoint. Orin appears disguised as an abducted companion and attempts to force the party into dealing with Gortash.
If Gandrel survives Act One and the relevant Astarion or Cazador storyline has progressed, he may appear near the Lower City Sewers waypoint with Chessa and Kass.
Guildhall
Nine-Fingers is not simply a shopkeeper or quest-giver. She is the political centre of the Guild’s response to the Stone Lord and Zhentarim pressure. The Guildhall’s outcome depends heavily on whether the party supports the Guild, helps its rivals or intervenes in the Stone Lord plot.
Murder Tribunal
The tribunal is a progression area rather than an ordinary settlement. Its residents are connected to Bhaal’s cult and to the legacy of the earlier Bhaalspawn crisis.
Ancient Lair
Mystic Carrion also appears above ground in Philgrave’s Mansion, so his surface residence should not be mistaken for a second Undercity location. The Ancient Lair is the hidden crypt and workshop relevant to his immortality and the Free the Artist resolution.
Undercity Ruins and Bhaal Temple
The named characters above are not all present at once or in the same progression state. Some are corpses, scripted encounters, quest-linked appearances or enemies rather than ordinary residents.
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The Guild
The Guild controls much of Baldur’s Gate’s organised criminal activity. Its headquarters in the Guildhall are both a social hub and a strategic base. The Guild is under pressure from the Stone Lord and has accepted Zhentarim support, not realising that the Zhentarim intend to replace it.
Zhentarim
The Zhentarim are present in the Guildhall through Nine-Fingers’ agreement. They are not neutral contractors. Their involvement is part of a wider attempt to gain power over Baldur’s Gate’s criminal infrastructure.
Stone Lord’s gang
The Stone Lord’s forces operate through the sewer and cistern plotlines connected with Minsc. Their presence makes the sewers more than a static dungeon: the area is an active battleground between competing criminal organisations.
Cult of Bhaal
The Cult of Bhaal dominates the northern Undercity. Its members conduct murders, stage ambushes, guard the temple and serve Orin’s leadership. The Murder Tribunal and Bhaal Temple represent different levels of the same religious and political structure.
Security and hazards
The Undercity has no unified law enforcement. Security is supplied by whichever faction controls a particular subarea:
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Sarin’s Skull
Near Bareki in the Undercity Ruins is a pouch containing Sarin’s Skull. This item is needed to bring peace to Sarin and resolve the related ghost encounter. Check the area around Bareki before proceeding into the main ruins.
Dribbles’ head
The corpse of Wilting Alex contains Dribbles’ head, one of the body parts required for Find Dribbles the Clown. This area is reached during the descent through the ruins towards the Bhaal Temple, so the quest cannot be completed until the party has gained access to this portion of the Undercity.
Whispering Statues
The stairway towards the temple is lined with Whispering Statues. They recite lines associated with Alaundo’s Bhaalspawn prophecy and provide lore about how the cult interprets the prophecy.
Manslaughter Chasm
Manslaughter Chasm is the main open battlefield in the Undercity Ruins. A narrow bridge crosses the chasm, while cliffs, elevated ledges and ruined structures create opportunities for ranged attacks and ambushes.
Ancient ruined buildings
The ruined structures around the chasm contain corpses, notes and small caches. One locked building can be opened with a Sleight of Hand check or a nearby Silver Key. Its upper level contains a corpse labelled “Unholy Diversions”.
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Bonespike Gloves
Strangler Luke carries the Bonespike Gloves. To obtain them, kill and loot Luke before defeating Ghislev. After the ambush ends, Luke’s body may despawn with the other Bhaalist corpses, making the gloves missable during that encounter.
Amulet of Bhaal
The Amulet of Bhaal is normally obtained through the Murder Tribunal and is required to open the Bhaal Temple doors after the Ghislev encounter. The item is central to the Bhaalist route and should not be discarded or left in storage before entering the ruins.
Sarin’s Skull
Required for Sarin’s ghost-related resolution. It is found in the Undercity Ruins near Bareki.
Dribbles’ head
Found on Wilting Alex during the descent towards the temple. It is one component of the larger Dribbles quest and is not a random drop.
Bareki’s stock
Voiceless Penitent Bareki sells items and alchemical ingredients in the Undercity Ruins. The exact shop inventory can vary with level and progression, so treat it as a trader encounter rather than a fixed list of unique rewards.
Sewer containers
The sewer network contains locked chests, traveller’s chests, pouches and scattered valuables. Some chests in the Knights of the Shield Hideout route contain gold, random valuables, potions or spell scrolls, with possible high rarity depending on the game state. These are container contents rather than guaranteed unique Undercity rewards.
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Main and faction quests
The Undercity can start, advance or conclude parts of the following activities:
Not every quest is wholly contained within the Undercity. Several only use it as one stage in a larger chain.
Main and faction quests
Orin’s kidnapping event
If Orin’s kidnapping has not already been initiated, entering certain sewer areas can trigger her approach. She appears disguised as a kidnapped companion, uses the appearance to manipulate the party and then reveals herself. She demands that the party kill Gortash in return for the victim’s life.
This is a progression-sensitive scene. The exact kidnapped character and trigger conditions depend on party composition and earlier actions.
The Murder Tribunal
The tribunal is the principal Bhaalist initiation route:
Players who do not want to follow the tribunal’s intended ritual can use alternative methods for the first ruins door, but the Bhaal Temple still uses its own progression requirements.
The Murder Tribunal: steps
- 01Investigate the murders in the Lower City.
- 02Follow the clues to Candulhallow’s Tombstones.
- 03Discover the hidden passage behind the funeral business.
- 04Enter the Murder Tribunal.
- 05Deal with Sarevok and the tribunal’s demands.
- 06Obtain the Amulet of Bhaal if following the relevant route.
- 07Return through the sewers to open the Undercity Ruins and Bhaal Temple doors.
Farslayer Ghislev
The Ghislev encounter is a set-piece battle across the Manslaughter Chasm. The leader begins a ritual and the surrounding Bhaalists join the fight as the party advances.
A high Perception result can reveal elements of the ambush before combat begins, but the fight is not entirely avoidable.
Practical priorities
- 01Identify Ghislev’s position and source of the ritual.
- 02Use long-range attacks, movement skills or invisibility to shorten the distance.
- 03Keep characters away from exposed bridge positions where possible.
- 04Search Luke’s body before the fight ends if you want the Bonespike Gloves.
- 05Continue to the temple only after confirming that needed loot has been collected.
Dark Urge progression
The Undercity Ruins and Bhaal Temple are especially important for the Dark Urge. Events in the temple create mutually exclusive outcomes involving the character’s Bhaalspawn identity, including embracing or rejecting Bhaal. These choices update The Urge and may affect Gather Your Allies.
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Stone-door mechanism
The hanging corpses above the first ruins door are not merely scenery. Shooting either corpse opens the passage. This is one of the most useful environmental solutions in the region.
Temple bridge traps
The bridge towards the Bhaal Temple contains Marble Plates and Sanguine Vents. Perception checks can reveal them, but a failed check does not make the bridge harmless. Move carefully, avoid unnecessary movement across suspicious surfaces and consider sending a character with good Perception ahead of the main group.
Spell Rot
The Ancient Lair imposes Spell Rot, which damages spellcasters when they cast spells. A martial character can lead the exploration, while the party reserves healing, buffs and high-value spells for the undead fight.
Ritual timing
The Ghislev fight changes depending on whether the ritual is triggered immediately or disrupted. If you want to explore the side building and loot Luke, do so before finishing the encounter.
Morphic Pool point of no return
Do not board the skiff to the Morphic Pool until you have:
Entering the Morphic Pool disables normal camp functions and party management for the endgame stretch.
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Before entering the Morphic Pool
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Is the Undercity the same as the Lower City Sewers?
No. The Lower City Sewers are the main subarea of the Undercity, but the wider region also includes the Guildhall, Abandoned Cistern, Murder Tribunal, Undercity Ruins, Ancient Lair, Bhaal Temple and Morphic Pool.
Can I reach the Bhaal Temple directly from the Lower City?
Not directly. The normal route is through the Lower City Sewers, then the Undercity Ruins, then the Bhaalist approach and Ghislev’s battlefield.
Do I need to complete the Murder Tribunal?
You can open the first ruins door without completing the tribunal by shooting the hanging corpses or casting Knock. However, the tribunal is the main route to the Amulet of Bhaal, which is required for the Bhaal Temple doors after Ghislev.
Where is the Undercity Ruins waypoint?
It is just north of the Lower City Sewers, after passing through the stone archway into the ancient ruined cavern. The location changes to Undercity Ruins at approximately X: -138, Y: 907.
Is the Murder Tribunal inside the sewers?
It is within the Undercity region but not normally connected to the sewer network. Its entrance is hidden inside Candulhallow’s Tombstones near the city graveyard.
Can I return after entering the Morphic Pool?
The Morphic Pool begins a point-of-no-return sequence for Act Three. You lose ordinary access to camp, stored equipment, party changes and Withers respec services during the endgame route. Finish your preparation first.
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The game’s visual boundaries between the Lower City Sewers, Abandoned Cistern and Guildhall are deliberately fluid, and the sewer article itself describes them as ambiguous. This guide follows the game’s location labels and the established regional hierarchy rather than treating every visually similar tunnel as one map.
The Undercity character category contains 131 entries, including minor named enemies, corpses, ghosts, scripted figures and characters whose presence depends on quest state. A fully exhaustive character directory would require checking each category entry against its precise subarea and progression conditions. The directories above therefore prioritise verified residents, named quest figures, traders, faction leaders and named encounters relevant to the region, rather than claiming that every category entry has been reproduced.
Sources
- Undercity - bg3.wiki — bg3.wiki
- Lower City Sewers - bg3.wiki — bg3.wiki
- Undercity Ruins - bg3.wiki — bg3.wiki
- Bhaal Temple - bg3.wiki — bg3.wiki
- Undercity Ruins - bg3.wiki — bg3.wiki
- Lower City Sewers - bg3.wiki — bg3.wiki
- Category:Characters in the Undercity - bg3.wiki — bg3.wiki