10 D&D Underdark adventure hooks
Updated: Apr 11, 2023
Welcome to our guide to 10 D&D Underdark Adventure Hooks! If you're a Dungeon Master looking for inspiration for your next campaign, or a player interested in exploring the depths of the earth, you've come to the right place.
The Underdark is a vast network of caverns, tunnels, and subterranean cities that lies beneath the surface world. It's a dangerous and mysterious place filled with terrifying monsters, ancient civilizations, and valuable treasures. The Underdark is also home to many of the most popular races in Dungeons & Dragons, including the Drow, Duergar, and Deep Gnomes, each with their own unique cultures and customs.
In this guide, we've compiled 10 adventure hooks and concepts that will take you and your party on a journey through the depths of the Underdark. From battling dragons and undead armies to navigating complex political alliances and conspiracies, these adventure hooks offer a wealth of highly detailed information that can help you craft a thrilling campaign that will keep your players on the edge of their seats.
We've included a range of ideas to suit all kinds of parties and playstyles, from combat-heavy campaigns to more political and diplomatic adventures. Whether you're running a Forgotten Realms campaign set in one of the most popular regions of the Underdark, or exploring a new world entirely, this guide is a valuable source of inspiration and ideas that will help you create a memorable and exciting adventure for your players. So grab your light sources, sharpen your melee weapons, and get ready for a lot of fun in the depths of the earth!
There are potential common threads that unite these adventures together and a possible two part mega finale (see adventures 9-10), so if you were looking to create a mega campaign in the Underdark, there is potential for that here.
Title: The Duergar Lord's Demise
Background Content: The Duergar, a race of dark dwarves, have long been considered one of the most cunning and treacherous races of the Underdark. Recently, a powerful Duergar lord has emerged and is making deals with other evil factions, including Mind Flayers, to expand his power and control over the Underdark.
Adventure Hook: The party members are hired by a group of Deep Gnomes, who have been at war with the Duergar lord for years, to infiltrate his stronghold and put an end to his reign of terror. The party must navigate through intricate caverns filled with aberrant monsters and new trapdoors, while also avoiding the overconfident explorer who has stumbled upon the same dungeon.
Main Villain: Kaal the Duergar lord is the main villain, and he is not to be underestimated. He has amassed a small army of shock troops and has several high elves and noble houses under his control. The party must use all of their resources, including magic items and their own unique PC races, to defeat the Duergar lord and his minions.
Plot Hooks: Along the way, the party may discover a valuable source of gemstones that the Kaal has been hoarding, a crystal ball that can reveal the exact location of otherworldly contact, and a small village of dead prospectors that have fallen prey to the Duergar's darkest impulses. In addition, the party may encounter a psychic lost in the caverns who warns them of the Duergar lord's plans and gives them a quest to retrieve an object of legendary power that could be used to defeat him.
Additional Material: This adventure idea could be adapted to fit into a Forgotten Realms campaign setting, and could also include new regional feats, new prestige classes, and new monsters from the Monster Manual or other sources. It would also be a good opportunity for the Dungeon Master to showcase the wealth of highly detailed information available in the Underdark campaign setting, including the intricate caverns of the Underdark, the various below-ground character races, and the society of the Drow.
Title: The Curse of the Drow City
Background Content: The Drow are one of the most popular Underdark races, and their society is highly complex and dangerous. Recently, a powerful Drow matron, Ungradh, has fallen under a curse that has caused her to lose control of her city and her people. As a result, the Drow are on the brink of civil war, and their surface world allies are calling for help.
Adventure Hook: The party members are tasked with entering the cursed Drow city of Nulus and finding a way to break the curse before it's too late. Along the way, they must navigate intricate caverns, avoid deadly traps, and fight off monsters such as monstrous spiders and hook horrors. The party must also uncover the source of the curse and defeat the main villain, a powerful demon who has infiltrated the city and is manipulating the Drow.
Main Villain: The main villain is the powerful demon, Othgor, who has infiltrated the Drow city and is behind the curse. The demon has his own agendas and will stop at nothing to maintain his hold over the Drow and their valuable resources.
Plot Hooks: Along the way, the party may discover a neutral ground where members of different Underdark races are meeting to discuss a new trade deal, a forgotten Drow temple that holds deep-tunnel artifacts of great power, and a seafaring adventure that takes them to the depths of the earth in search of the demon's lair.
Additional Material: This adventure idea could include new PC races, such as high elves and duergar, and new monsters from the Monster Manual or other sources. It could also incorporate the wealth of detailed information available in the Forgotten Realms campaign setting, including the society of the Drow and the depths of the Underdark.
Title: The Warlock's Abandoned Dungeon
Background Content: The Warlock Zenedth, a powerful wizard who dabbled in dark magic, was thought to have been defeated long ago. However, recent reports indicate that the Warlock's abandoned dungeon has been reactivated and is once again a source of danger.
Adventure Hook: The party members are hired by a wealthy adventurer to investigate the Warlock's abandoned dungeon and find out what is causing it to come back to life. Along the way, they must fight off new monsters that have infested the dungeon, including aberrant monsters and pitch-black horrors.
Main Villain: The main villain is Zenedth himself, who has returned from the dead and is using the dungeon as a base of operations to carry out his twisted experiments and rituals.
Plot Hooks: Along the way, the party may discover a hidden entrance to the dungeon that leads them to the ceiling of a cavern, a series of intricate caverns that are home to a tribe of deep gnomes who have their own reasons for wanting the Warlock defeated, and an above ground clamour that threatens to interfere with the party's mission.
Additional Material: This adventure idea could include new monsters, traps, and magic items, as well as new trapdoors and underground sites of interest. It would also be a good opportunity to showcase the wealth of detailed information available in the D&D 5th edition, including the extensive story content and the challenge ratings of monsters.
Title: The Dying plague of Escalioth
Background: In the Underdark, there is a Drow city, Eascalioth, known for its wealth and power. However, the city is afflicted, and its inhabitants have been suffering from a mysterious disease that drains their life force. The city's rulers have been unable to find a cure for the illness, and tensions within the city are rising. The party is hired by a powerful noble from the city to investigate the source of the curse and find a way to lift it.
Plot Hook: The party is hired by a Drow noble to investigate the curse that has been afflicting the city's inhabitants. The noble provides the party with information about the curse and a map of the city. The party must navigate the city's intricate caverns and dark alleyways, fighting off Drow guards and uncovering clues about the curse's origins. Along the way, the party can choose to ally with different factions within the city, each with their own motives and agendas.
Main Villain: As the party investigates the curse, they discover that it is the result of an evil ritual performed by a powerful Drow priestess, Nayasa. The priestess is attempting to use the curse to gain control of the city and overthrow its rulers. The party must stop her before she completes the ritual and unleashes a dark power that could destroy the city and its inhabitants.
Additional Content: The adventure can include new traps, magic items, and it can also feature the drow society and their culture, as well as the depths of the earth and the underground world. The party can encounter hook horrors and aberrant monsters, as well as neutral ground and other factions that may help or hinder them in their quest. The adventure can also have an extensive story content with twists and turns, giving the players a good opportunity to explore and delve deeper into the Drow city's history and politics.
Title: Tomb of the Undead Kings
Background: In the Underdark, there is an ancient tomb filled with the remains of powerful undead kings. The tomb is said to contain a valuable source of gemstones that is guarded by the wights. The party is hired by a wealthy merchant from the surface world to retrieve the gemstones and bring them back to the surface.
Plot Hook: The party is hired by a wealthy merchant from the surface world to retrieve a valuable source of gemstones from an ancient tomb in the Underdark. The merchant provides the party with a map of the tomb's location and warns them of the undead that guard the tomb. The party must navigate the tomb's intricate passages and chambers, fighting off undead creatures and avoiding deadly traps.
Main Villain: As the party makes their way through the tomb, they discover that a powerful necromancer has taken control of the undead kings and is using their armies to wage war on the surface world. The necromancer has been gathering power and resources in the Underdark for years, and the party's intrusion threatens to disrupt his plans. The party must defeat the necromancer and his undead minions before they can launch their attack on the surface world.
Additional Content: The adventure can include new traps, magic items, and extensive story content. The party can encounter monstrous spiders and other undead creatures, as well as explore the intricate caverns of the Underdark. The adventure can also feature a crystal ball that provides clues and hints to the party, as well as a ceiling of a cavern that can be used to ambush or evade enemies. The party can also discover the necromancer's own agendas and motivations, as well as the noble houses of the Underdark who may have their own interests in the tomb's contents.
Title: Dragon's Lair
Background: In the depths of the Underdark, a powerful black dragon has made its lair. The dragon's presence has upset the delicate balance of power among the various factions of the Underdark, and its hoard of treasure is a valuable prize for any who can claim it. The party is hired by a group of duergar who seek to eliminate the dragon and claim its treasure for themselves. This adventure might even be run as an evil version of the Hobbit.
Plot Hook: The party is hired by a group of duergar to eliminate a powerful dragon that has taken up residence in the Underdark. The duergar provide the party with a map of the dragon's lair and offer a reward for the dragon's head. The party must navigate the treacherous tunnels of the Underdark and confront the dragon in its lair.
Main Villain: The dragon, Azar, is the main villain of the adventure. It is a powerful and cunning creature, with many loyal minions and traps in its lair. The dragon may be hostile to the party from the outset, or it may be willing to negotiate for a share of its hoard. Either way, the party must defeat the dragon and claim its treasure.
Additional Content: The adventure can include new traps, magic items, and extensive story content. The party can encounter underground rivers and lakes, as well as large caverns that serve as the dragon's lair. The adventure can also feature a seafaring adventure, as the party navigates underground rivers and lakes to reach the dragon's lair. The dragon's minions may include shock troops, hook horrors, and other aberrant monsters. The party may also encounter dead bodies of previous adventurers who failed to defeat the dragon. The adventure can also include a multitude of Forgotten Realms products, such as the Drow campaign setting and the Warlock's abandoned dungeon.
Title: Battle for the Caverns
Background: In the depths of the Underdark, a powerful group of elementals has risen up against the lizardfolk who have long held sway in the region. The elementals seek to dominate the area and harness the power of the earth itself, while the lizardfolk seek to protect their ancestral territory. The party is called upon by a group of lizardfolk to aid them in defeating the elemental uprising and restoring balance to the region.
Plot Hook: The party is approached by a group of lizardfolk who seek their aid in defeating a group of powerful elementals who have risen up against them. The lizardfolk provide the party with information about the elementals' lair and offer a reward for their assistance. The party must navigate the treacherous tunnels of the Underdark and confront the elementals in their lair.
Main Villain: The main villains of the adventure are the powerful elementals who seek to dominate the region. The elementals are led by a powerful earth elemental who seeks to harness the power of the earth and bend it to his will. The party must defeat the earth elemental and its minions to restore balance to the region.
Additional Content: The adventure can include new monsters, magic items, and extensive story content. The party can encounter underground lakes and rivers, as well as intricate caverns filled with traps and puzzles. The adventure can also feature the lizardfolk as a playable race, with new racial feats and abilities. The elementals may be aided by fire creatures or other elemental monsters, while the lizardfolk may have access to magic or powerful allies of their own. The adventure can also feature a multitude of Forgotten Realms products, such as the Forgotten Realms campaign setting and the duergar fief of Gracklstugh.
Title: Shadow Conspiracy
Background: The party discovers an evil plot by a group of shadar-kai who have formed a pact with a group of dire trolls. The shadar-kai seek to control the dire trolls and use them to wage war on the other denizens of the Underdark, while the dire trolls seek to feed their insatiable hunger. The party must uncover the conspiracy and stop the shadar-kai before they unleash their dire troll army on the Underdark.
Plot Hook: The party is hired by a group of drow who have discovered evidence of a sinister plot by a group of shadar-kai who have formed an alliance with a group of dire trolls. The drow fear that the shadar-kai will use the dire trolls to overthrow their rule and plunge the Underdark into chaos. The party must investigate the conspiracy and put an end to the shadar-kai's plans.
Main Villain: The main villains of the adventure are the shadar-kai who seek to control the dire trolls and use them to wage war on the Underdark. The shadar-kai have formed a pact with a powerful dire troll leader who seeks to feed its insatiable hunger by devouring the other inhabitants of the Underdark. The party must confront the shadar-kai and the dire trolls to put an end to their evil scheme.
Additional Content: The adventure can include new monsters, magic items, and extensive story content. The party can encounter the shadar-kai and their mysterious shadow magic, as well as the savage and powerful dire trolls. The adventure can also feature new trapdoors and intricate caverns of the Underdark, as well as the ancient ruins of long-lost civilizations. The adventure can also feature a multitude of Forgotten Realms products, such as the Forgotten Realms campaign setting and the drow city of Menzoberranzan. The party may also have to contend with other factions who have their own agendas in the region.
Title: Diplomatic Tensions
Background: Tensions have risen between the various races of the Underdark, and a full-blown war seems imminent. The party is tasked with mediating between the different factions and preventing the war from breaking out. The party must navigate a complex web of political intrigue, alliances, and rivalries to find a peaceful solution to the conflict.
Plot Hook: The party is summoned by a powerful drow house to negotiate a treaty between the various factions of the Underdark. The drow fear that a war between the different races will lead to the destruction of their city and the destabilisation of the entire region. The party must use their diplomatic skills to bring the different factions to the negotiating table and find a peaceful solution to the conflict.
Main Villain: The main villains of the adventure are the hardliners among the different factions who seek to escalate the conflict and push their own agendas. These factions include militant factions of drow, duergar, and other races who seek to gain power or territory in the region. The party must find a way to appease these factions or neutralise their influence to prevent the conflict from escalating.
Additional Content: The adventure can include high-level diplomacy, political intrigue, and negotiations between the different factions. The party must use their skills to persuade the different factions to make concessions and reach a compromise. The adventure can also feature new prestige classes and regional feats that reflect the unique abilities and cultures of the Underdark races. The party may also have to contend with outside forces who seek to take advantage of the instability in the region. The adventure can feature multiple potential endings depending on the party's choices, with a peaceful resolution being the most difficult to achieve.
Title: Uniting the Underdark
Background: Despite the party's best efforts, the diplomatic negotiations fail, and the different factions of the Underdark go to war. The party is called upon by a powerful drow house to help unite the various factions and lead them in the fight against a common enemy. The party must overcome mistrust and rivalries between the different races to form a coalition and turn the tide of the war.
Plot Hook: The party is summoned by a powerful drow house to help unite the various factions of the Underdark against a common enemy. The drow fear that if the various factions do not band together, they will be crushed by their enemies. The party must navigate a complex web of politics and rivalries to build a coalition and lead the fight against their enemies.
Main Villain: The main villains of the adventure are the leaders of the enemy factions who seek to conquer the Underdark and destroy their enemies. These factions include hordes of aberrations, undead, or other monsters that have been unleashed by a powerful and malevolent force. The party must find a way to unite the different factions of the Underdark to face this threat and turn the tide of the war.
Additional Content: The adventure can include building alliances and gaining the trust of the different factions of the Underdark, leading troops into battle against the enemy forces, and uncovering the source of the malevolent force behind the war. The party may also have to contend with traitors and spies who seek to undermine their efforts and sow mistrust between the different factions. The adventure can feature new magical items, powerful artefacts, and epic battles against the enemy forces. The party's success or failure in uniting the different factions of the Underdark will determine the fate of the region and its people.
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