Heroes, beware. Undermountain awaits those foolhardy or brave enough to walk its passages, but step lightly and with care. Undermountain's welcome is not that of a gracious friend who seeks to make you comfortable. Learn more about this superadventure by reading a few excerpts, including the introduction, various adventure sections, plus a couple of encounters.
Just after dawn, a long, rolling earthquake shakes the city awake. Cracks appear in walls and crockery rattles, but no buildings collapse.
REALMSLORE: EVENT DATE
If you want to use this adventure in a Forgotten Realms campaign, then the earthquake occurs just after a bright dawn on the last day of Eleint in the Year of Risen Elfkin (1375 DR).
Uproar ensues. Earthquakes are almost unheard of in the city. Rumors of disaster soon race through the streets, fueled by the anguish of people across the city whose heads fill with sharp, sudden mental visions of a screaming bearded man whose eyes blaze with rage, sorrow, and swimming stars. The visions shift into scenes of pillars cracking and tumbling, ceilings collapsing in caverns and dark rooms, and surging explosions of blue-white sparks. These tides of fearsome force leave many who receive the visions gasping on their knees, unharmed but overwhelmed by the sensation of great magical forces crashing through them. Repeatedly the screaming face returns, with feelings of strong despair, of something left unfinished -- and swept away in great loss and ruin. What has happened? A few wizards across the city who shared the disturbing visions recognize the screaming face as that of Halaster Blackcloak, the infamous "Mad Mage of Undermountain."
Soon everyone knows that something terrible has happened in Undermountain. There's an unknown but exceedingly dark doom approaching the city and the massive dungeon beneath it, and Halaster is very upset about it.
Those who have experienced the visions can't stop thinking of Undermountain, of walking through its chambers, of finding brightly glowing treasures. They yearn to go there, to answer Halaster's urgent call. Undermountain awaits, in desperate need. Something down there must be repaired, or renewed, or rescued. Halaster wants something done now, something vital. A terrible calamity must be set right, or greater doom will surely come.
That night, wizards, sorcerers, a scattering of adventurers, and others across the land dream of Undermountain and a screaming Halaster. They all feel a yearning to enter the infamous, legendary dungeon and do "something that must be done." No one quite knows what that something is, but many momentarily mind-glimpse strange subterranean rooms, weird items, and a rushing Halaster struggling to accomplish various tasks.
Throughout the land, on the morning after the earthquake, wizards, sages, and all sorts of adventurers start packing. The trek to Undermountain has begun.
REALMSLORE: A BRIEF HISTORY OF UNDERMOUNTAIN
The great dungeon of Undermountain was built by dwarves some twenty-six centuries ago. It was conquered, in turn, by drow, duergar, and powerful wizards.
King Melair I discovered a vein of mithral beneath what would one day be known as Mount Waterdeep in -1,288 DR. Under his able rule, the foundations of the Underhalls of Melairbode were laid. The elf city of Aelinthaldaar occupied the surface above the Underhalls, and the dwarves and elves struck a bargain that has tied the two regions together to the current day.
In the year 168 DR, the wizard Halaster Blackcloak and his apprentices (known as the Seven) came to area. His goal was to explore the Underhalls and claim them as his own. He initiated nine expeditions (known as Halaster's Hunts) to brutally exterminate the drow and duergar who had driven out the dwarves in centuries past. By 309 DR, Halaster ruled the Underhalls.
The Seven (Arcturia, Jhesiyra Kestellharp, Muiral the Mishapen, Nester, Marambra Nyghtsteel, Rantantar, and Trobriand) broke ties with Halaster in 307 DR in the hope of establishing their own holdings in the great depths beneath the mountain. Some left signs of their work that can still be seen today, but most of the Seven went insane or perished chasing their own dreams and desires. Only Jhesiyra escaped Halaster's clutches, eventually becoming the Magister of Myth Drannor in 658 DR.
Beginning in 713 DR, Halaster and his apprentices embarked on a massive campaign to fill the dungeon with all manner of monsters and treasure. For many centuries, the land above forgot about the Underhalls, and in 889 DR the town of Waterdeep was established. It quickly grew in size and influence. However, the long centuries of monster population growth led to an invasion of the surface in 1037 DR. After repelling the invasion, the lords of Waterdeep struck an agreement with Halaster, urging him to keep the monsters of Undermountain in check.
In 1148 DR, the Netherese wizard Shradin petitioned Halaster for permission to establish Skullport. Shradin became the Lord of Bones, and Skullport flourished.
In response to the explorations of two noted adventurers, the Yawning Portal Inn was established in 1306 DR to limit access into Halaster the Mad Mage's dungeon and to keep its monsters somewhat contained. This was also the year that Waterdeep began the practice of exiling the worst of its criminals to the depths of Undermountain.
Today, in response to a looming arcane disaster, Halaster attempted a ritual that resulted in the Mad Mage's death. As his soul shattered, he was able to send visions to those with arcane connections and ties to Undermountain, warning them of the coming danger and urging them to save his beloved domain.