## Encounter 1: Entering the Gem **Expected Duration:** 15–20 Minutes With all three locks opened, the Black Gem falls silent. Every rune carved beneath its surface ignites with pale silver light before slowly rotating into a single circular pattern. The crystal begins to hum, increasing in volume until the sound can be felt through the floor rather than heard. Hair, clothing and loose objects are drawn towards the Gem as though caught in a powerful current. The black crystal softens into a perfectly smooth surface resembling still water. Any creature approaching within 5 feet can see a faint reflection of themselves standing in an endless black void beyond the surface. A creature touching the Gem feels no resistance. Their hand passes through the surface as though entering cold water. A creature may willingly enter the Gem by stepping completely into the crystal. Any creature physically holding another creature entering the Gem is drawn through as well, allowing the party to enter together. Unwilling creatures cannot be pulled inside. Once the final willing creature has entered, the Gem hardens instantly, becoming an inert black crystal on the Material Plane. As the party passes through the Gem, each character experiences the same vision. They fall through complete darkness without sensation or direction while thousands of distant whispers speak names in languages long forgotten. Brief silhouettes of trapped souls drift past before disappearing into the void. Among them, one voice cuts clearly through the others. > "You came." The darkness suddenly gives way beneath their feet. The party arrives upon a circular platform of polished black stone suspended within an endless void. There is no visible sky, floor or horizon. Massive chains disappear into the darkness in every direction, each connected to distant fragments of floating ruins. A faint silver mist hangs over the platform, limiting visibility to approximately 120 feet. Behind the party, the portal closes without sound, leaving no obvious means of escape. Allow the party time to orient themselves. Characters may investigate the platform before proceeding. | Action | Result | | ---------------------------- | ------------------------------------------------------------------------------------------------------------ | | Inspect the platform | The stone bears thousands of shallow scratches made by humanoid hands and fingernails. | | Arcana DC 18 | The platform exists within a stable demiplane. Conventional teleportation magic cannot leave this plane. | | Investigation DC 15 | Several sets of footprints lead away from the platform but none return. | | Perception DC 20 | A faint female voice can occasionally be heard calling from somewhere beyond the mist. | | Detect Magic | The entire demiplane radiates overwhelming necromancy. No individual magical source can be distinguished. | | Cast Sending targeting Steve | The spell succeeds. Steve receives the message but can reply only with, "Find me... don't trust the voices." | Once the party leaves the arrival platform and follows any of the chained pathways into the mist, read no further description. Proceed immediately to Encounter 2. # Encounter 2: The Hall of Chains ## Room 1: The Prison Archive The first chamber resembles an immense library carved from polished black crystal. Shelves hold thousands of crystal prisms, each no larger than a human skull. Within every prism drifts a single soul, suspended in a perpetual state of awareness. Some silently weep, others endlessly relive their final moments, while many simply stare into the darkness with hollow resignation. Every prism bears an engraved plaque recording its prisoner's **True Name**, **Year of Imprisonment**, and **Soul Strength**. The oldest souls occupy the highest shelves, while newer arrivals are found closer to the entrance. Every few moments, a pulse of black energy ripples through the archive, causing every prism to briefly flicker. Searching the shelves eventually uncovers familiar names from throughout history, including adventurers, kings, priests and those who vanished within the Tomb of Horrors. After approximately ten minutes of searching, the party discovers Diamond Emberfoot's prism. > **Diamond Emberfoot** > **Year Imprisoned:** Present Day > **Soul Strength:** Exceptional Unlike every surrounding prism, Diamond's crystal remains perfectly clear. Black veins have not begun spreading through it, suggesting her imprisonment is still recent. Her soul notices the party's presence and desperately reaches towards the crystal wall, but no sound escapes. Continuing the search reveals another unusual prism. > > **Lord Robilar** > **Classification:** Primary Anchor > **Imprisoned:** 937 Years > **Soul Strength:** Prime > **Crimes Recorded** > - Murder of 143 companions. > - Deliberate sacrifice of innocents to bypass magical wards. > - Seven massacres committed in pursuit of forbidden relics. > - Betrayal of every sworn ally. > - Countless murders beyond record. Robilar's prison differs from every other. Hundreds of black crystal chains emerge from its base and disappear into the floor beneath the archive. Every pulse of black energy originates from his prism before spreading outward through the room. Characters examining multiple prisms eventually notice a pattern. **Investigation DC 16.** Every ordinary soul prism possesses a single crystal chain extending into the floor. **Investigation DC 20.** Every chain eventually converges beneath Robilar's prison. **Arcana DC 18.** The chains are not restraining Robilar. They are sustaining the prison itself. **Arcana DC 22.** Robilar's soul is functioning as a magical anchor. Every imprisoned soul within the Black Gem is connected to him. Searching the archive for maintenance records uncovers a damaged obsidian ledger resting upon a stone lectern. Most of its contents have decayed beyond recognition, but one surviving passage remains legible. > **"Primary Anchor stable. Secondary bindings nominal. Should the Primary Anchor fail, all subsidiary prisons will immediately terminate."** No entry identifies the Primary Anchor by name. If the party has successfully connected Robilar's prism, the converging chains and the surviving maintenance record, they may conclude that Lord Robilar is the Primary Anchor maintaining every prison within the Black Gem. Releasing or destroying his prison would collapse the archive and free every imprisoned soul simultaneously. Whether doing so is wise remains unanswered. ## Room 2. Feeding Chamber When the party enters this chamber, read: > Twelve identical bodies of Acererak kneel around a suspended black crystal. Every few moments the crystal pulses and a trapped soul is drawn from the darkness below. The soul is divided into twelve fragments, each entering one of the kneeling bodies. Every clone opens its eyes, smiles, and exhales before rapidly decaying into dust. Black liquid immediately reforms each body, and the cycle begins again. ### Investigating the Chamber **Arcana DC 18.** The bodies are not true clones. They are empty vessels created for a single purpose. **Arcana DC 22.** The soul is not consumed by the vessels. They merely transfer its energy elsewhere. **Legend Lore.** The vision reveals Acererak creating the chamber, using imprisoned souls to sustain his immortality. ## Room 3. The Warden's Door When the party reaches the third chamber, read: > An immense obsidian door blocks the passage ahead. Set into its centre are two empty recesses. The first is a perfect circular socket, the second is shaped like a humanoid hand. Above them, a single inscription has been carved into the stone. > > **"The jailer enters only with his prison."** The door cannot be forced open. It is immune to all damage and unaffected by magic. ### Opening the Door The circular recess perfectly matches one of the soul prisms recovered from the Prison Archive. The hand-shaped recess perfectly matches the hand of one of the Acererak vessels from the Feeding Chamber. Placing only one item into its recess has no effect. When both are placed into the door simultaneously, the obsidian surface ripples and the inscription glows silver. The door slowly slides open before both recesses release their contents unharmed. ### Development The party learns that every section of the Black Gem was designed to function together. The prison cannot be accessed without both a prisoner and a jailer, reinforcing that the prison and Acererak's phylactery are parts of the same creation.