Adventure Summary: A one-session supernatural horror siege for four to five 8th-level characters. As Hollowmere begins its final memorial vigil, the reservoir rises against a clear sky and every drowned spirit marches toward the old dam. The party must hold four lantern wards, open Widow’s Gate, and give the Mourning Tide a truthful place among the living.
Hollowmere Lantern Saga: Part 4 of 4. This adventure stands alone. Previously: The House Beneath the Reservoir. This concludes the Hollowmere Lantern Saga.
Overview
Hollowmere’s council has finally scheduled a public vigil for everyone erased by the flood. At sunset, the reservoir rises six feet despite clear weather. Pale watchers fill dark windows, four ward lanterns ignite on their own, and a human-shaped wave presses its face against the old dam.
The entity is the Mourning Tide, the combined memory of those denied a proper record. It is not satisfied by destruction or apology alone. Before midnight, the party must protect the village, complete the memorial circuit, and operate Widow’s Gate using the true flood charter or a surviving valve diagram.
Background
Every false ledger, stolen breath, censored portrait, and unmarked grave fed the same spiritual pressure beneath Hollowmere. Restoring individual names woke the greater memory. The Mourning Tide now demands to be witnessed by the living, but its attempt to enter every mind at once will drown the village in remembered terror.
Standalone hook: Mara supplies a newly recovered copy of the charter, Ysabet knows the vigil hymn, and the council offers 1,500 gp to defend Hollowmere. Saga hook: The Warden’s Wick, Breathglass Rosary, Tideglass Key, rescued allies, and restored truths each grant a specific advantage, but ordinary tools and checks provide equivalent routes so earlier play is never required.
Characters
- Mara Vell: Now the public warden of the complete memorial. She coordinates the four lantern posts and refuses to conceal her family’s role.
- Sister Ysabet: Leads the vigil hymn and keeps frightened residents moving between shelters. She believes Cadoc’s procession can become an honor guard.
- The Lantern Widow: If previously released, Elowen appears as an ally. Otherwise she arrives hostile but can be reconciled with the true charter during play.
- The Mourning Tide: A colossal archive of grief. It speaks through hundreds of overlapping voices and attacks any attempt to reduce the truth to a convenient slogan.
Setting
The Watch House, Lantern Green, Pilgrim Inn, Flooded Chapel, Sluice Tower, Bone Orchard, Old Dam, and Widow’s Gate form a defense circuit. Four ward lanterns stand at the Green, Chapel, Orchard, and Gate. Residents can shelter at the Inn or evacuate by the Coach Road.
Track four Vigil rounds, each representing roughly an hour. In every round, the party chooses two crises to address personally while allies manage the rest. An unresolved crisis adds one Dread mark. At three Dread, villagers panic and abandon one ward. At four, the finale begins with the dam cracked, but no failed scene removes the possibility of victory.
Plot Outline
The party assigns defenders, secures the Lantern Green, rescues residents at the Pilgrim Inn, consecrates the Bone Orchard, negotiates with the Lantern Widow, repairs the Sluice Tower, and faces the Mourning Tide on the Old Dam. Victory comes from completing the memorial circuit and opening Widow’s Gate, defeating the Tide’s manifestation, or persuading it to inhabit the beacon.
1. Prepare the Vigil
Give the party twelve villagers, Mara, Ysabet, two boats, four lanterns, and three bundles of repair supplies. Assigning defenders to the Green, Inn, Chapel, and Gate requires four DC 14 Investigation, Persuasion, Survival, or relevant tool checks. Each success grants one automatic crisis success later. Failure reveals a weak point and adds no Dread yet.
2. Lantern Green
Drowned Vigilants advance through flooded lanes while Name Lanterns call defenders away. The party must earn three DC 15 Arcana, Athletics, Performance, or Religion successes while holding the central flame. A Warden’s Wick grants one automatic success. Failure adds Dread, but Mara saves the lantern and retreats it to the Watch House.
3. The Pilgrim Inn
A wall collapses as spectral water fills the upper floor. Twelve residents must cross a rope to the Coach Road. Run three DC 15 Acrobatics, Medicine, Persuasion, or thieves’ tools successes before two failures. Breathglass protects six residents automatically. Failure adds Dread and costs each rescuer 2d6 bludgeoning damage, but no civilian dies without a clear player choice.
4. Bone Orchard
The unmarked dead rise around the ward lantern. Ysabet can lead their hymn while the party places four name boards. Each board requires an action and DC 15 History, Religion, or calligrapher’s supplies. Drowned Vigilants attack anyone carrying blank boards. Completing all four turns the dead into a protective procession and removes one Dread.
5. The Widow’s Demand
Elowen appears at the Sluice Tower and demands the true charter. If the party presents it without excuses, she joins the defense. Otherwise, earn three DC 16 Insight, Persuasion, or History successes while surviving her attacks. Prior reconciliation counts as two successes. At 18 hit points she pauses, and naming her alongside the laborers completes the negotiation.
6. Repair the Sluice
The valve sequence requires four stations operated in order: Green, Chapel, Orchard, Gate. Characters earn four DC 16 Athletics, Arcana, Investigation, or thieves’ tools successes. The Tideglass Key creates calm water and grants advantage at two stations. Each failure adds Dread and releases a jet requiring a DC 15 Dexterity save for 3d6 bludgeoning damage.
7. The Last Vigil
At midnight, the Mourning Tide rises over the Old Dam with two Drowned Vigilants per Dread mark. At initiative count 20, it floods a platform, extinguishes an unattended light, or projects a memory requiring a DC 16 Wisdom save against frightened. The party needs four memorial successes using DC 16 Religion, Performance, Persuasion, or the recovered truths, plus three valve successes using DC 16 physical or technical checks. Damage can disperse the Tide at 0 hit points, but unless the beacon receives at least one memorial success it reforms next year. At 30 hit points, it listens.
8. Resolution
Opening Widow’s Gate lowers the reservoir without flooding the village. The Mourning Tide enters the four-wicked beacon, allowing every name to be heard during an annual, safe vigil. Elowen, Cadoc, and the house spirits pass on or remain gentle guardians according to the party’s choices. Hollowmere survives, the council publishes the full charter, and the saga ends without requiring any sequel.
NPCs and Monsters
| NPC or Monster | Statistics | Key Abilities and Table Notes |
|---|---|---|
| Mara Vell | Medium humanoid; AC 12, HP 27, speed 30 ft. | Lanterncraft +6. Once per round, grants advantage on a ward, ledger, or civilian protection check. She carries the central flame and never conceals the charter. |
| Sister Ysabet | Medium humanoid; AC 12, HP 33, speed 30 ft. | Religion +7, Medicine +6. Her homecoming hymn grants advantage against fear or forced movement. She maintains the Orchard ward unless civilians need healing. |
| Lantern Widow | Medium undead; AC 15, HP 78, fly 30 ft. (hover). | Cold Grasp +7 and Naming Gaze, DC 15 Wisdom. She becomes an allied guardian when shown the true charter and named alongside the laborers. |
| Mourning Tide | Huge undead; AC 18, HP 168, swim 60 ft. | Memory Surge +9 deals 3d8 + 5 psychic and moves 15 feet. Archive of Grief, DC 16 Wisdom save, frightens. It listens at 30 HP and can inhabit the completed beacon. |
| Drowned Vigilant | Medium undead; AC 16, HP 58, speed 30 ft., swim 30 ft. | Ward Breaker +6 deals 2d6 + 4 bludgeoning, or 4d6 + 4 to an object. A complete name board within 20 feet suppresses its reactions and siege damage. |
Rewards
- 1,500 gp in council bonds and recovered Hale silver, plus permanent hospitality in Hollowmere.
- Hollowmere Beacon: This four-wicked lantern sheds bright light in a 30-foot radius. Once per dawn, its bearer can ask the spirits of a place one question about an event witnessed there.
- The Village Remembers: Each hero’s name is entered in the public ledger. Hollowmere’s guardians provide safe passage through the reservoir region.
Scaling the Adventure
For a 7th-level party, reduce the Mourning Tide to 145 hit points and cap Drowned Vigilants at four. For a 9th-level party, raise the Tide’s save DCs to 17 and let it use Flood Platform as a bonus action once per round. For a shorter session, begin after preparations with the Green and Inn secured, then run the Orchard, Sluice, and final vigil.
Memorial-Vigil-Horror-Themed Table Gear
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- Flickering lantern string lights. Mark the four ward positions and visibly extinguish one when a crisis is lost.
- Large vigil hourglass. Give each abstract hour a physical countdown during the village defense.
- Modular stone dam terrain. Build Widow’s Gate, cracked platforms, and changing flood lanes for the finale.