**D&D 5e Adventure Module: The Depths of Kalteo** _An endgame adventure for characters of level 15–17_ --- ### **Adventure Overview** **Summary:** In the heart of Kalteo, a prison lies buried beneath the city’s foundations. Built long ago to contain what should not exist, the prison now serves as the harvesting grounds for Big Tony’s horrific ambitions. Deep within, an Eldritch Horror is chained, its essence siphoned to power the flying city. With the Hand of Vecna in Tony's possession, the party must descend through this twisted dungeon, decide the fate of the horror, and stop Tony before he tears the city’s future apart. **Adventure Hooks:** - The flying city begins to tremble and darken as the crystals powering it start to shatter. - A warning from a rogue Archon or one of Kalteo's magical engineers points the party underground. - The Sordia Vignti receive a direct challenge from Big Tony, daring them to stop him. **Key Objectives:** - Descend the layers of the prison beneath Kalteo. - Survive escalating magical corruption and Syndicate resistance. - Discover the origins of the Eldritch Horror and its connection to the city's power. - Defeat Big Tony and retrieve the Hand of Vecna. - Choose to kill or free the Horror and face the consequences. --- ## **Level 1: The Forgotten Gaol – Fully Detailed** ### 📖 Narrative Setup > The stone walls groan with the weight of centuries as you descend through the rusted iron hatch. A faint, choking chill clings to your skin. Motes of ghostly light drift down the prison corridor, flickering like dying stars. Beyond the bars and ruins, whispers echo — not voices, but regrets, grief, hatred. The Forgotten Gaol remembers its inmates... and it does not forgive. ### 🧭 Area Overview - Layout: Two-tier prison with administrative ruins above and haunted cell blocks below. - Objective: Retrieve four enchanted keys to unlock the elevator to the next level. ### 🧟 Encounters - **Wailing Prisoners:** (3 Wraiths, DC 17 Wis save or frightened). - **Fleshbound Jailers:** (4 Ghouls with metal masks, resistant to slashing). - **Phantom Jailer Mini-boss:** Phasing undead with lair actions. ### 🔍 Exploration Sites 1. **Cursed Cell:** Whispers of loved ones; DC 18 Wis or stunned. 2. **Collapsed Mess Hall:** Ghouls fight amid slippery debris. 3. **Graveyard:** Skill challenge to find the correct grave, or fight skeleton knights. 4. **Phantom Patrol:** Jailer ambushes players at random until defeated. ### 🧩 Puzzle – Elevator Activation - Insert keys in correct sequence (Blood, Bone, Flesh, Mind). - Mistakes cause 5d6 psychic damage (DC 16 Int save for half). ### 🌟 Secrets - Hidden Shrine of Ilmater: Religion DC 16 to gain a 24h Blessing of Protection and scroll of _Greater Restoration_. --- ## **Level 2: The Arcane Extraction Wing – Fully Detailed** ### 📖 Narrative Setup > Blue lightning dances through the air, humming against arcane pylons. Grotesque machines wheeze, their glass tubes housing unconscious figures drained of magical essence. The very stone here pulses with harvested energy — the stolen breath of Kalteo's victims. ### 🧭 Area Overview - Layout: Mad alchemical labs fused with prison tech. - Objective: Survive the unstable magic and confront the horrors of Tony’s energy extraction. ### 💥 Hazards & Wild Magic - Spell failures on natural 1–2; caster takes 2d10 force damage. - Arcane surge nodes release random Wild Magic effects every 3 rounds. ### 🧟 Encounters - **Crystalfused Aberrations:** Twisted Otyugh-like creatures with explosive death bursts. - **Arcane Defenders:** Floating pylon guardians that discharge chain lightning. ### 🧙‍♂️ NPC: Matheron Vox - Mad former Syndicate mage. - Reveals that the Horror predates the city and once served as a gate guardian. - Offers temporary resistance to wild magic zones if calmed (DC 18 Persuasion). ### 🎯 Optional Objective - Free the unconscious captives to weaken the Horror’s chains and gain divine favour. --- ## **Level 3: The Ritual Chambers – Fully Detailed** ### 📖 Narrative Setup > Black braziers cast flickering azure light on walls etched with endless spirals. Hooded figures chant in forgotten tongues, tracing the outline of an ancient creature whose limbs seem to shift each time you blink. The rituals are not yet complete... ### 🧭 Area Overview - Layout: Series of ritual sanctums surrounding a central altar. - Objective: Solve the sin seals and defeat Kivaros. ### ✨ Puzzle: The Three Sin Seals 1. **Greed:** Balance golden scales perfectly. 2. **Pride:** Solve a riddle: “What weighs nothing, but binds all who boast?” (Answer: Ego). 3. **Wrath:** Show mercy to a bound, snarling cultist. Killing resets all seals. ### 🧟 Encounters - **Cultists:** Warlocks with _Maddening Whispers_ (confusion aura). - **Living Runes:** Trap glyphs that float and lash with psychic damage. ### 👹 Boss: Kivaros, Tony’s Lieutenant - CR 15 Tiefling Warlock. - Wields _Whisperblight_, a sentient sword that casts _Hunger of Hadar_. - Lair Action: Void hands grapple from beneath (DC 18 Dex or restrained). --- ## **Level 4: The Crystal Core – Fully Detailed** ### 📖 Narrative Setup > You descend into an impossible chamber of floating crystal pillars, their glow casting kaleidoscopic shadows. Gravity bends strangely here. At the center, the Horror slumbers, its chained limbs entwined with the city's veins of light. It is aware of you. It has always been aware. ### 🧭 Area Overview - Layout: Radial arena of floating platforms. - Objective: Make the final choice — free or kill the Horror. ### 🧟 Encounters - **Crystal Guardians:** Explode in radiant shards on death. - **Crystallised Beholders:** One awakens if players make noise (CR 13). ### 🧠 Roleplay Sequence - The Horror speaks in dreams or mind whispers. - It offers gifts: power, knowledge, even resurrection. - Insight check (DC 20): reveals it once defended reality, now corrupted. ### ⚔️ Choice Point - **Free It:** Kalteo’s crystals begin failing. Evacuation starts. - **Kill It:** Initiate massive multi-phase boss battle. - Tentacle phases. - Void-beam cones. - Psychic lash lair actions. --- ## **Level 5: The Vault of Chains – Fully Detailed** ### 📖 Narrative Setup > Chains thick as towers tether a throne of obsidian bone. Upon it lounges Big Tony — resplendent, grinning, a glowing green Hand clasped over his chest. Around him, reality shudders. “Took you long enough,” he says, as shadows coalesce into claws. ### 🧭 Area Overview - Layout: Wide coliseum-style arena. Pillars collapse each round. - Objective: Defeat Big Tony and stop the Horror’s final fusion. ### 💀 Final Boss: Big Tony **Phase 1:** - Legendary Actions: Necrotic Burst (3d10 in 20 ft), Shadow Teleport, Grasping Hand. - Spells: _Power Word Kill_, _Finger of Death_, _Dominate Monster_. **Phase 2:** - Tony is absorbed by the Horror: _Eldritch Tony_ (CR 21). - Gains tentacle reach, cone of madness, and lair actions every round. **Phase 3 (Optional):** - If the Horror was freed, the final battle is a 3-way collapse. Time limit to escape or seal the prison. --- ## **Conclusion & Fallout** **Victory:** - Hand of Vecna recovered. - Kalteo saved (if Horror was slain) or crumbles slowly (if freed). - Major NPC factions react (Archons, Celestial Syndicate remnants, etc.). **Defeat:** - Kalteo destabilises. - Vecna’s influence grows unchecked through the escaped Horror. - Party may be imprisoned, lost, or hunted. **Rewards:** - _Whisperblight_ (Artifact, sentient, hunger for void energy). - _Crystalcore Blade_ (Greatsword, radiant/psychic swap, pulse ability). - _Tony’s Ledger_ (Insight on underworld, grants contacts and advantages). --- ## **Appendices** **Stat Blocks:** (Can be added next) - Big Tony (Vecna Warlock + Horror Boons) - Eldritch Horror Core (colossal aberration) - Kivaros (Tentacle Warlock) - Crystalfused Aberrations (Aberration/Construct hybrid) **Handouts:** - Ritual blueprints. - Eldritch warning scroll. - Map of the prison layout. - Vision Journal from Ilmater’s last follower. **Optional Maps:** - Layered prison design, elevator descent. - Final arena (Vault of Chains) with collapsing zones and chaos orbs. Let me know if you’d like the stat blocks or printables created next.