Designed for an adventuring party of four to six 1st-level characters, Baldur’s Gate: Descent into Avernus is a Dungeons & Dragons adventure that begins in the city of Baldur’s Gate and ends in Avernus, the first layer of the Nine Hells. By the end of the adventure, the characters should be 13th level or higher. To run this adventure, you need the fifth edition Player’s Handbook, Dungeon Master’s Guide, and Monster Manual.
Use the first session of the game to help your players create their 1st-level characters. As part of this process, the players can choose their party’s dark secret (see “area Dark Secrets").
Adventure Overview
The holy city of Elturel has disappeared from the Forgotten Realms and descended into Avernus, the first layer of the Nine Hells. This event came about as the result of an infernal bargain between the archdevil Zariel, who rules Avernus, and the treacherous High Overseer of Elturel, Thavius Kreeg. Zariel is capturing cities and using their citizens as fodder in the ongoing conflict between demons and devils known as the Blood War. Next on Zariel’s list of cities is Elturel’s neighbor, Baldur’s Gate. The characters can be the heroes who descend into Avernus, save Elturel from certain destruction, and prevent a similar fate from befalling Baldur’s Gate.
Trouble in Baldur’s Gate
Chapter 1 begins in the independent city of Baldur’s Gate, where the characters find themselves trapped behind the city’s walls after the gates are sealed to keep out hundreds of refugees from the neighboring land of Elturgard. However, the gates can’t hold back news that Elturgard’s capital has fallen, and that Grand Duke Ulder Ravengard of Baldur’s Gate is missing—lost on a diplomatic mission to Elturel. The fact that Elturel’s misfortune coincided with Ravengard’s visit has left Baldurians wondering whether Baldur’s Gate will suffer Elturel’s fate.
The characters are drafted by the Flaming Fist, the army of mercenaries tasked with protecting Baldur’s Gate. Without Grand Duke Ulder Ravengard to lead them, the Flaming Fist mercenaries are little more than glorified thugs. The characters' orders are to help maintain peace by rooting out and destroying followers of Bane, Bhaal, and Myrkul—evil gods collectively known as the Dead Three. These vile priests, assassins, and necromancers are murdering city folk at random, and the Flaming Fist is too distracted and disorganized to hunt them down and find their lair. In the course of their investigation, the characters learn that the Dead Three cultists are secretly being financed by Thalamra Vanthampur, one of three remaining dukes who preside over the government of Baldur’s Gate, using money stolen from the hoard of Tiamat, the evil queen of dragons imprisoned in the Nine Hells.
With Grand Duke Ulder Ravengard out of the way, Thalamra is paying the Dead Three to shatter confidence in the Flaming Fist so that all payments to the decapitated organization can be cut off. Thalamra, a devout disciple of the archdevil Zariel, has brokered a deal that will enable her to claim the role of grand duke once the Flaming Fist disbands, paving the way for the city’s descent into Avernus. To accomplish this last goal, Thalamra needs an artifact called the
To keep Baldur’s Gate from falling into Zariel’s clutches, the characters must take the shield far away from the city. Reya Mantlemorn, a young knight from Elturel, suspects that the Vanthampurs are sheltering Thavius Kreeg at their estate and offers aid. Characters who storm Duke Vanthampur’s villa find Thavius hidden in the dungeon below it. Thavius is helping Thalamra Vanthampur use the
Visit to Candlekeep
In the course of dealing with Thavius Kreeg and the Vanthampur family, characters are likely to acquire the
If the characters wish to help Baldur’s Gate further, they must journey to the Nine Hells and rescue Ulder Ravengard from what’s left of Elturel. The characters are urged to seek out Sylvira Savikas in Candlekeep. Sylvira knows the secret to unlocking Thavius’s puzzle box. She can also facilitate the characters' descent into Avernus and provide them with a map (albeit an unreliable one). Sylvira advises characters to leave the
To the Nine Hells!
Chapter 2 opens with the characters' arrival in Elturel, which is anchored by enormous chains and trapped under the baleful light of the Companion. If the characters do nothing, the city will be pulled down into the River Styx and bound to the Nine Hells forever. Lulu tries her best to serve as the party’s guide in Avernus, but the hollyphant’s memories are fragmented. It becomes clear, however, that Lulu has a personal connection to Zariel, dating back to the archdevil’s former angelic existence.
After scouring Elturel for survivors and clashing with the denizens of Avernus, the characters encounter the valiant Ulder Ravengard, who has been placed in the most unusual situation of defending a city he has long opposed. The beleaguered Ravengard urges the characters to do whatever they can to free Elturel and return what’s left of it to Faerûn. To do so, they must scour Avernus for the means to destroy the Companion or break the enormous chains that shackle that city, as described in chapter 3.
Avernus has long been a battlefield in the never-ending Blood War. Apart from clashing demons and devils, petty warlords scour the Avernian wastelands in search of treasure, salvage, and fuel for their infernal war machines. Characters who forge an alliance with one warlord risk alienating the others. By acquiring an infernal war machine, characters can travel quickly across Avernus—a domain rife with tortured souls, warmongers, and devils eager to tempt would-be heroes into soul-corrupting deals.
The more time she spends with the characters, the more Lulu begins to remember long-lost memories of the
The characters' success doesn’t hinge on acquiring the
As tempting as such pursuits can be, the characters must be careful, for devil deals, demon lords, and Tiamat’s rage number among the multiverse’s greatest threats. Also, Zariel herself might become cross with the characters for daring to meddle in her diabolical affairs. How the adventure concludes depends on the choices the characters make, the chaos they foment, and the deals they forge, as discussed in chapter 5.
Adventure Background
On the plane of Mount Celestia, the angel Zariel chastised her peers for not getting involved in the Blood War. She felt that it was the responsibility of the angelic host to destroy evil in the multiverse, rather than stand back and watch demons and devils annihilate one another, destroying vast swaths of the multiverse in the process. In defiance of her superiors, Zariel left Mount Celestia and went to Elturel, where she rallied an army of warriors and trained them to fight in the Blood War. She promised them that when they were ready, she would lead them into battle on Avernus.
Zariel led her army out of Elturel amid a throng of cheering well-wishers and proud citizens in 1354 DR. In an epic charge known as the Ride, Zariel’s army entered Avernus and took the fight to the archdevil Bel and his infernal legions. Many of Zariel’s warriors fought bravely, but for others, the horrors of the Nine Hells proved too great. They fled back through the portal, sealing it behind them and never revealing their shameful retreat and betrayal. The Hellriders, as they were called, would wear this badge of shame to the grave.
Zariel’s Fall
Zariel lost more than her army on Avernus. She also lost a hand, which was severed in battle. As her sword fell to the ground, Zariel ordered Yael, her most devoted general, to take the weapon and hide it, so that the devils would not destroy or corrupt it. Yael took the sword and fled, along with Zariel’s faithful hollyphant companion, Lulu. Zariel’s other two generals, Olanthius and Haruman, refused to leave Zariel’s side. All three were captured and sent to Nessus, the lowest of the Nine Hells. There, Zariel was brought before Asmodeus, who welcomed her with open arms. The Lord of the Nine commended Zariel for her battle prowess and the strength of her convictions. He offered her rulership of Avernus, much to Bel’s chagrin. By swearing fealty to Asmodeus and the Nine Hells, Zariel could bring her rage to bear against the demons and continue to fight in the Blood War, with legions of devils under her command. Zariel accepted Asmodeus’s terms, completing her fall from grace. Haruman followed his master into damnation willingly and was transformed into a narzugon devil, while Olanthius, who took his own life rather than bow before Asmodeus, was brought back to serve as a death knight under Zariel’s burning gaze.
The Companion
Zariel never forgot her betrayers—those who ran from the battlefield. She kept a close eye on Elturel, waiting for the day when she could enact her revenge. That day came in 1444 DR, when Elturel was conquered by a vampire lord. A priest of Torm named Thavius Kreeg appealed to any power to help him save his holy city. In that instant, Zariel emerged from a pillar of fire and offered him a deal, which Thavius readily accepted.
In the sky over Elturel, a radiant sphere called the Companion appeared, blazing like a second sun. Powered by a planetar imprisoned within it, the Companion bathed Elturel and the surrounding countryside in holy light which sent the vampire lord scrambling for the shadows and laid waste to his undead army. Thavius Kreeg, who took credit for summoning the Companion, was hailed as the savior of the city and rose to become its high overseer. Under Kreeg’s decades-long rule, Elturel embarked on a path to becoming not just a holy city but the holy nation of Elturgard.
Thavius’s Betrayal
Thavius was told the exact time when the Companion would cease to protect Elturel. In the weeks leading up to this fateful hour, Thavius urged Grand Duke Ulder Ravengard of Baldur’s Gate to visit Elturel, to help settle some longstanding disputes between the two cities. Facing political pressure at home, Ravengard reluctantly acceded. After greeting Ravengard’s delegation, Thavius Kreeg fled Elturel in secret and watched from a safe distance as the Companion transformed from a radiant sun into a black orb awash with crackling energy. It ripped Elturel from the Material Plane, transporting it and all its inhabitants to Avernus. A few other city folk managed to escape before Elturel disappeared. Where it once stood, only a crater remains.
Disguised as a refugee, Thavius Kreeg was one of the first of his people to arrive at Baldur’s Gate with news of Elturel’s “destruction.” He slipped through the city’s gates with the help of his influential friend, Duke Vanthampur, and took refuge in her home.
Roleplaying Devils
As the DM, you can play devils as humorous, aloof, bombastic, conniving, or scatterbrained, but a general rule to follow is this: devils have no desire to do good. When dealing with mortals, devils are constantly figuring out how to exploit and corrupt them, often behind thin smiles of feigned concern and false charm.
A devil that successfully corrupts a mortal gets the infernal equivalent of a gold star and can eagerly expect a superior to take notice and give it the promotion it so richly deserves. Meanwhile, when that mortal dies, its soul will find itself condemned to the Nine Hells where it twists into the form of a lemure (unless it’s used for some other morbid purpose). The devil doesn’t care what becomes of the souls it corrupts; it just wants to be promoted to a superior form of devil. That’s how, over ages, a lemure might become a pit fiend.
But devils do more than corrupt. They also fight in the Blood War. Asmodeus attests that serving in his infernal legion is a holy honor, for in so doing a devil helps protect the multiverse from demonic destruction. While that sounds impressive, most devils partake in the Blood War only to distinguish themselves among their peers and move up the chain of command. Endlessly fighting demons isn’t what most devils signed up for.
If a devil dies somewhere other than the Nine Hells, it re-forms in the Nine Hells and is therefore not truly killed. However, a devil that is killed in the Nine Hells is dead forever; not surprisingly, that’s why devils tend to be more cautious in their dealings at home than abroad.
Important References
This adventure features the Nine Hells, which is described in chapter 2 of the Dungeon Master’s Guide. Devils, being the primary inhabitants of the Nine Hells, play prominent roles in this story. Before running the adventure, it’s worth taking the time to familiarize yourself with the “Devils” entry in the Monster Manual, which not only describes the most common types of devils but also explains their hierarchy, how they behave in accordance with their lawful evil alignment, what pleases and enrages them, and why they’re scared of dying on their home plane.
Stat Blocks: The Monster Manual contains stat blocks for most of the monsters and nonplayer characters (NPCs) found in this adventure. Whenever this adventure presents a new monster or NPC, you’ll find its stat block near the encounter in which it appears, or in appendix D. When a creature’s name appears in bold type, that’s a visual cue pointing you to the creature’s stat block in the Monster Manual. If the stat block appears elsewhere, the adventure’s text tells you where to find it.
Spells and Magic Items: Spells and nonmagical equipment mentioned in the adventure are described in the Player’s Handbook. Magic items are described in the Dungeon Master’s Guide, unless the adventure’s text directs you to an item’s description in appendix C.
Devil Traits
Common traits among devils include the following:
Charm. Devils are consummate charmers. Like humans, some are better at it than others. The good ones savor the exchange of pleasantries, speaking in measured sentences or noticing pleasant details about the environment or a character’s clothing.
Patience. Devils are rarely in a rush to make a deal or sign a contract. As masters of the long con, devils make genuinely good deals with mortals to buy appreciation and trust that can be leveraged during more consequential dealings later on.
Civility. Devils like to pretend that they run by the same rules and obey the same social conventions as mortals. Devils have no problem appearing and acting in whatever manner they need to achieve their end goal—usually a contract for services or a soul. They’ve learned that more can be gained from behaving in a civilized manner than reacting angrily or violently.
Deviousness. Devils don’t age, so there’s rarely a sense of urgency with a devil as it plots its conquest or corruption of a soul. This allows for winding schemes that are rarely what they seem on the surface. For minor devils, a simple acceptance of an evil gift is enough, while greater devils enjoy tangling up characters in choices that compromise their values.
Unscrupulousness. Being evil and soulless, a devil cannot be embarrassed or shamed, doesn’t feel guilt or remorse, and is prepared to do the most heinous acts to get what it wants.
Fear of Demotion. A devil that disappoints a superior can be demoted, whereupon it’s instantly transformed into a lesser form of devil. The greater the devil, the more it fears demotion and the loss of its power. Thus, a devil takes great pains to hide its failures or pin them on someone else.
Life in the Nine Hells
Much of the adventure takes place on the first layer of the Nine Hells. This is not, to put it mildly, your run-of-the-mill D&D setting. The following tips and tricks can help you make the characters' stay in Avernus a remarkable one.
Everyone’s Unhappy
The Nine Hells is a place of abject misery where no one is happy. Weaker devils are exploited and tormented by their superiors. Stronger devils live in constant fear of being passed over for promotion or demoted. Even when something seems to go right, joy is fleeting and only fuels suspicion that things are about to get much worse. Such inescapable pessimism leads many creatures to become apathetic and spiteful. They take perverse delight in spreading their unhappiness like a contagion.
You can remind players that the Nine Hells is a place of misery and suffering in the following ways:
- In conversations with the characters, natives of the Nine Hells like to bemoan their misfortune and blame others for their horrible lives.
- When a character accomplishes something, you can undercut that success in some small way. For example, the character’s belt might snap, or a hellish insect might sting the character on the neck and leave a welt.
- If a character rolls a natural 1 on an attack roll made with a nonmagical weapon, you can decide that the weapon breaks.
Everything’s Awful
Avernus is insidious in the way it fosters greed and makes visitors pay or barter for the things they need to survive. Most of the wildlife on Avernus is not edible to mortals, and most sources of water are poisonous or otherwise tainted. The rarity of edible food and drinkable water encourages hoarding behavior.
You can remind players about the awfulness of Avernus in the following ways:
- Any food or drink the characters bring with them or conjure by magic retains its nutritional value but tastes awful when eaten or imbibed on Avernus. The food tastes like ash, the water tastes like bile, and the wine tastes like spoiled milk.
- If the characters want something that tastes good, they must buy it from licensed sellers such as Mahadi the rakshasa, who runs a restaurant called Infernal Rapture (see “area Infernal Rapture"). The price of a good-tasting meal is always a bit too high.
- If a character commits a selfish act, you can reward that selfishness by granting that character inspiration (as described in chapter 4 of the Player’s Handbook). Unlike regular inspiration, the benefit can’t be transferred to another creature.
Paradise Lost
Before the Blood War reduced it to a blasted wasteland, Avernus was a honey trap created by Asmodeus, a paradise of infinite delights designed to lure and enrapture mortals. Fragments of this lost paradise still plunge from Avernus’s sky as burning meteors, and the land is dotted with the ruins of palaces and idyllic gardens that were obscenely beautiful in eons past.
Fleeting reminders of this ancient paradise can come to the characters in the following ways:
- While traveling across Avernus, the characters glimpse a fantastic mirage: a grand palace or garden oasis that vanishes when they get within 100 feet of it.
- A random character hears beautiful music or laughter, catches the scent of flowers or perfume, or experiences a gentle caress. The sensation has no discernible source and fades after a few moments.
- The characters find a relic that survived the fall of paradise, such as a beautiful vase or toppled statue. The first character to touch the relic experiences a fleeting moment of pure joy.
Anywhere is Everywhere
Geography warps at the whims of the Nine Hells. One of the liberating aspects of this planar feature is that you don’t need to be fastidious about keeping track of where locations are in relation to one another.
While the spatial distortion can be unsettling to visitors, it affords you the following benefits as a DM:
- You can decide how long it takes for characters to get from one place to the next. For example, the characters might need to travel 6 miles to get from Fort Knucklebone to Haruman’s Hill, and 60 miles to get from Haruman’s Hill back to Fort Knucklebone.
- If the characters are in a rush to get somewhere, an imp could appear out of nowhere and, for the price of a
soul coin or other valuable item, show them a shortcut that halves the distance the characters must travel to reach their destination. - The Wandering Emporium (see “area The Wandering Emporium") can show up almost anywhere in the Nine Hells, at any time. If the players don’t know where to go or what to do next, or if you want to surprise them with fun roleplaying opportunities, have the Wandering Emporium arrive at the party’s location, regardless of where they saw it last.
That Personal Touch
There are simple ways in which you can tailor the adventure to make Avernus an even more hellish place for your particular band of adventurers. Consider using the following methods to customize your party’s experience:
- Learn what scares the characters. At the start of the adventure, ask each player to provide you with a note of three things their character fears. Save these until the party reaches the Nine Hells, then use them to customize the terrors that populate Avernus.
- Keep a list of the flaws that the players selected when they first created their characters, so that you can remind the players of these faults when situations arise to test them. For example, a character with the Folk Hero background might have the flaw, “I’m quick to assume that someone is trying to cheat me.” Let the player wrestle with this flaw during negotiations with devils and other denizens of Avernus.