Wings Over the Wine-Dark Sea
One-Shot · 6 Players · Level 10 · ~3–3.5 Hours · Trireme Naval · Harpies & Sirens
📜 Session Summary
| Style Naval Skirmish — Aerial → Charm → Aberrant Boss (entirely on/around the trireme) |
| Win Condition Protect the ship and defeat Lampetia, Fog-Mother (0 HP or force her to sink/flee) |
| Players 6 × Level 10 · Duration 3–3.5 hrs |
| Minis used Harpy (≤10), Mermaid-as-Siren (≤4), Merman (≤3), Jellyfish caster (≤5), Sea spirit (≤5); optional 2nd fog-skiff |
| Setting Open Mediterranean — trireme deck under attack → fog-shrouded open water → fog-skiff boarding encounter; no solid ground at any point |
| Atmosphere Vast and exposed; the sea is indifferent and the weather is hostile; every threat arrives from above or below, never from the front |
| Materials Conch of Relative Silence (handout); ship-deck battle map (40×50 ft + bow/stern); wave-height tracker; fog-clock |
| Tone Mythic sea-horror — beauty that kills slowly, isolation that makes every decision feel final |
Description
Through Misthaven’s mist the party is already aboard their trireme when a Thetis-touched envoy warns that a siren chorus — amplified by jellyfish fog-witches — is hunting sails. Optional sea spirits may aid or clutter the fog. All three encounters play on the wine-dark deck under wings and song.
Trireme Map
Main deck 40×50 ft · raised bow +15 ft · raised stern +25 ft · 90 ft total length (tapered ends) · center mast/sail · 15 ft ram at bow. Board supports up to 2 additional ships. Optional 2nd ship: a low fog-skiff (30×15 ft) carrying jelly-witches in Enc. 3.
Major Beats
- Mist-trireme: envoy + Conch.
- Enc. 1: Harpies dive the sail.
- Enc. 2: Sirens (mermaids) + consorts — song vs. steel.
- Enc. 3: Fog-skiff arrives; Lampetia + jelly-witches.
Session Rewards
Keepable prizes earned by completing (or excelling at) this session. One character claims each reward unless noted. Full cards are under Reward Cards.
| Reward | Description | Criteria |
|---|---|---|
| Conch Echo of Relative Silence | Pale conch remnant that muffles siren song for a breath. | Shatter the Fog-Mother's song; the broken conch leaves a hush that still answers. |
Creature / Enemy List
| Creature | Easy | Med | Hard | Notes |
|---|---|---|---|---|
| Harpy | 4 | 6 | 8 | Enc. 1 / 3 |
| Siren | 2 | 3 | 4 | Enc. 2 |
| Siren Consort | 1 | 2 | 3 | Enc. 2 |
| Jelly-Witch | 2 | 3 | 4 | Enc. 3 |
| Lampetia | 1 adj | 1 | 1 | Boss |
Act 1 — Talons on the Sail
The sky is grey and the fog is already close when the first shape drops out of it — a harpy, then two more, then six, diving in loose formation on the trireme's sail. They do not attack the crew first. They attack the sail. The Luring Song starts on round 2, a sound like grieving turned into music, and every humanoid on deck feels the pull toward the nearest cliffside that isn't there.
Encounter 1 — Talons on the Sail
Overview
6× Harpies dive from fog. Win: drive them off; keep ≥1 sail section intact for a long rest before Enc. 2.
🗺 Terrain
Full trireme deck. Sail: 3 sections (each AC 11 / HP 15). Harpies prefer sails.
Mechanics
- Luring Song DC 11 targets crew first.
- Athletics DC 12 to climb rigging (½ cover).
- Non-combat: Performance DC 14 contest vs. song to confuse 2 harpies into leaving (1/encounter).
- ≥1 sail survives → Long Rest. All destroyed → Short Rest only (row).
Creature Cards
Harpy
Medium Monstrosity, Chaotic Evil · CR 1 (200 XP) · Mini ×10
AC 11 | HP 38 (7d8+7) | Speed 20 ft., fly 40 ft.
Skills: Performance +5
Luring Song. 30 ft.; DC 11 Wisdom. Charmed + incapacitated, move toward harpy. Repeat end of turn. Ends if damage taken / deafened.
Sail Priority. On the trireme, harpies attack the sail unless a PC is in melee reach.
Claws. +3 to hit. Hit: 6 (2d4+1) slashing.
Club. +3 to hit. Hit: 3 (1d4+1) bludgeoning.
Act 2 — The Sea Begins to Sing
The fog comes in after the harpies leave — thick, salt-smelling, rolling over the bow and rail. Then the singing starts below the waterline: three clear voices, harmonized, coming from the water itself. The sirens' heads surface at the bow and stern simultaneously, and the Siren Song begins at full intensity. On the eastern flank, three merman consorts are already climbing the ram.
Encounter 2 — The Sea Begins to Sing
Overview
3× Sirens + 2× Consorts approach the ram and stern. Fog banks roll in (light obscurement).
🗺 Terrain
Trireme + water within 20 ft. Overboard: Athletics DC 13 to climb the ram or oar-ports.
Mechanics
- Non-combat path: Group challenge — stop ears / outsing them (Performance/Religion/Conch) 4 successes before 3 failures (DC 14). Success: sirens withdraw; gain clue about Fog-Mother.
- Combat path: song + boarding. Conch pulses auto-succeed song saves in 10 ft for 1 round.
- RECRUITMENT: Spare a siren → Enc. 3 warning (adv Insight vs Lampetia’s illusion fog).
Creature Cards
Siren (Mermaid reskin)
Medium Fey, Chaotic Neutral · CR 2 (450 XP) · Mini: Mermaid ×4
AC 13 | HP 45 (7d8+14) | Speed 10 ft., swim 40 ft.
Skills: Performance +8, Persuasion +6 | Magic Resistance: adv on saves vs spells
Siren Song. 300 ft. (water/air); DC 14 Wisdom. Charmed 1 minute; must Dash toward siren. Deafened creatures immune.
RECRUITMENT. If spared after Enc. 2 and Persuasion/Performance DC 14, one siren may warn of the Fog-Mother (adv on Enc. 3 Insight).
Multiattack. Two dagger attacks.
Dagger. +5 to hit. Hit: 5 (1d4+3) piercing.
Drowning Embrace (Recharge 5–6). One charmed creature within 5 ft. DC 13 Strength or pulled underwater / overboard (Styx-style: Athletics DC 13 to board).
Siren Consort (Merman)
Medium Humanoid, Neutral · CR 1 (200 XP) · Mini ×3
AC 14 (sharkskin) | HP 32 (5d8+10) | Speed 10 ft., swim 40 ft.
Skills: Athletics +4
Boarding Hook. Advantage on Athletics to climb the ram or hull.
Trident. +4 to hit, reach 5 ft. or range 20/60. Hit: 5 (1d6+2) piercing.
Net (1/day). Range 5/15; Large or smaller DC 12 Dex or restrained.
Conch of Relative Silence
Wondrous Item (maguffin), Unique
Appearance: pale conch etched with closed lips
Handout (21 words). "When wings blot the sail and the sea begins to sing, breathe this shell — deafness is mercy, and mercy is a blade."
Enc. 1–2. Action: you and allies within 10 ft. auto-succeed saves vs. siren song until end of your next turn (1/short rest).
Enc. 3. Action: shatter the conch’s silence-pulse (once) — all siren/jelly casters DC 15 Con or lose concentration and song for 1 round; deals 20 thunder to the Fog-Mother if she is within 30 ft.
Act 3 — Fog-Mother Lampetia
The fog thickens past natural density — not weather, pressure. A second ship emerges from it: a flat-bottomed fog-skiff, thirty feet long, crewed by three jelly-witches trailing bioluminescent tendrils over the rail. At the skiff's center, Lampetia stands without moving. She is larger than she looked in the fog, and the grapple lines come over the rail before the party has time to react. The skiff locks to the trireme with a grinding sound. Two harpies drop from the fog above. The singing does not stop.
Encounter 3 — Fog-Mother Lampetia (Boss)
Overview
A fog-skiff (2nd ship, 30×15) grapples the starboard rail. Lampetia + 3× Jelly-Witches + 2× Harpies.
🗺 Terrain
Trireme + fog-skiff parallel. Grapple lines (AC 12 / HP 10 each; 3 lines). Mast = climb/fly perch.
Mechanics
- Win: Lampetia 0 HP or skiff sunk (HP 50) while she is aboard and Conch pulse used → she flees into the deep.
- Conch finale pulse: once, as item card.
- Persistence: no gods slain; Fog-Mother is aberrant, killable.
Creature Cards
Lampetia, Fog-Mother of Sirens
Large Aberration (Jelly-Queen), Chaotic Evil · CR 9 (5,000 XP) · BOSS · Mini: Jellyfish caster (large staging)
AC 16 | HP 161 (14d10+84) | Speed 20 ft., swim 40 ft., fly 30 ft. (hover)
Saves: Dex +7, Wis +7, Cha +8 | Resistances: lightning, psychic, BPS nonmagical | LR 2/day
Chorus Nexus. While ≥1 Siren is within 60 ft., her Siren Dirge DC is 16 instead of 15.
Shipboard Presence. Lairs on the fog-skiff (2nd ship) or hangs from the mast if the skiff is destroyed.
Multiattack. Three sting tendrils, or two tendrils and Dirge.
Sting Tendril. +8 to hit, reach 15 ft. Hit: 12 (2d8+3) piercing + 10 (3d6) poison.
Siren Dirge (Recharge 5–6). 60 ft.; each creature of her choice DC 15 Wisdom or charmed+incapacitated 1 min (repeat end of turns). Deafened immune.
Sow Fog-Witches (1/day). Summons 2 Thalassic Jelly-Witches in fog within 30 ft.
Tendril (Cost 1). One sting tendril.
Drift (Cost 1). Fly/swim 20 ft. without provoking.
Call Wings (Cost 2). 2 Harpies within 120 ft. each make one claws attack.
Thalassic Jelly-Witch
Medium Aberration, Neutral Evil · CR 3 (700 XP) · Mini: Jellyfish caster ×5
AC 13 | HP 58 (9d8+18) | Speed 20 ft., swim 30 ft., fly 20 ft. (hover, fog only)
Resistances: lightning, psychic | Immunities: poisoned
Fog Veil. While lightly obscured by fog, ranged attacks vs. it have disadvantage.
Sting Aura. Creatures that hit it with melee take 3 (1d6) poison.
Multiattack. Two sting tendrils.
Sting Tendril. +5 to hit, reach 10 ft. Hit: 7 (1d8+3) piercing + 7 (2d6) poison; DC 13 Con or poisoned 1 min.
Cast Fog (2/day). As fog cloud centered on self, 40-ft. radius, 10 minutes.
Harpy
Medium Monstrosity, Chaotic Evil · CR 1 (200 XP) · Mini ×10
AC 11 | HP 38 (7d8+7) | Speed 20 ft., fly 40 ft.
Skills: Performance +5
Luring Song. 30 ft.; DC 11 Wisdom. Charmed + incapacitated, move toward harpy. Repeat end of turn. Ends if damage taken / deafened.
Sail Priority. On the trireme, harpies attack the sail unless a PC is in melee reach.
Claws. +3 to hit. Hit: 6 (2d4+1) slashing.
Club. +3 to hit. Hit: 3 (1d4+1) bludgeoning.
⚖️ Difficulty Scaling
As Written ★ — 6 Players, Average Level 10
- Baseline for this guide. Encounter 1–2 are Hard; the final encounter is Deadly for six PCs at average level 10.
- XP budgets (6×L10 thresholds): Hard ≈ 10,800 · Deadly ≈ 16,800. Prefer adding elite pressure, legendary actions, or terrain danger over bloating minion counts past the choke.
Library Standard — 6 Players, Average Level 8
- Dial back: reduce boss HP ~20–25%; cut one legendary action option or recharge breath to 6 only; Favor/track thresholds −1 where present; skill DCs −1; drop one minion wave or −2 CR1–2 creatures from Hard openers.
Easier
- APL 8–9: use the Library Standard (6×L8) box, then shave one more minion wave or remove one recharge ability.
Harder
- APL 11–12: boss HP +20%; +1 legendary; final encounter gains one extra elite or lair pulse; skill DCs +1.
📋 Appendix — Cards
Creature Cards
Harpy
Medium Monstrosity, Chaotic Evil · CR 1 (200 XP) · Mini ×10
AC 11 | HP 38 (7d8+7) | Speed 20 ft., fly 40 ft.
Skills: Performance +5
Luring Song. 30 ft.; DC 11 Wisdom. Charmed + incapacitated, move toward harpy. Repeat end of turn. Ends if damage taken / deafened.
Sail Priority. On the trireme, harpies attack the sail unless a PC is in melee reach.
Claws. +3 to hit. Hit: 6 (2d4+1) slashing.
Club. +3 to hit. Hit: 3 (1d4+1) bludgeoning.
Siren (Mermaid reskin)
Medium Fey, Chaotic Neutral · CR 2 (450 XP) · Mini: Mermaid ×4
AC 13 | HP 45 (7d8+14) | Speed 10 ft., swim 40 ft.
Skills: Performance +8, Persuasion +6 | Magic Resistance: adv on saves vs spells
Siren Song. 300 ft. (water/air); DC 14 Wisdom. Charmed 1 minute; must Dash toward siren. Deafened creatures immune.
RECRUITMENT. If spared after Enc. 2 and Persuasion/Performance DC 14, one siren may warn of the Fog-Mother (adv on Enc. 3 Insight).
Multiattack. Two dagger attacks.
Dagger. +5 to hit. Hit: 5 (1d4+3) piercing.
Drowning Embrace (Recharge 5–6). One charmed creature within 5 ft. DC 13 Strength or pulled underwater / overboard (Styx-style: Athletics DC 13 to board).
Siren Consort (Merman)
Medium Humanoid, Neutral · CR 1 (200 XP) · Mini ×3
AC 14 (sharkskin) | HP 32 (5d8+10) | Speed 10 ft., swim 40 ft.
Skills: Athletics +4
Boarding Hook. Advantage on Athletics to climb the ram or hull.
Trident. +4 to hit, reach 5 ft. or range 20/60. Hit: 5 (1d6+2) piercing.
Net (1/day). Range 5/15; Large or smaller DC 12 Dex or restrained.
Thalassic Jelly-Witch
Medium Aberration, Neutral Evil · CR 3 (700 XP) · Mini: Jellyfish caster ×5
AC 13 | HP 58 (9d8+18) | Speed 20 ft., swim 30 ft., fly 20 ft. (hover, fog only)
Resistances: lightning, psychic | Immunities: poisoned
Fog Veil. While lightly obscured by fog, ranged attacks vs. it have disadvantage.
Sting Aura. Creatures that hit it with melee take 3 (1d6) poison.
Multiattack. Two sting tendrils.
Sting Tendril. +5 to hit, reach 10 ft. Hit: 7 (1d8+3) piercing + 7 (2d6) poison; DC 13 Con or poisoned 1 min.
Cast Fog (2/day). As fog cloud centered on self, 40-ft. radius, 10 minutes.
Lampetia, Fog-Mother of Sirens
Large Aberration (Jelly-Queen), Chaotic Evil · CR 9 (5,000 XP) · BOSS · Mini: Jellyfish caster (large staging)
AC 16 | HP 161 (14d10+84) | Speed 20 ft., swim 40 ft., fly 30 ft. (hover)
Saves: Dex +7, Wis +7, Cha +8 | Resistances: lightning, psychic, BPS nonmagical | LR 2/day
Chorus Nexus. While ≥1 Siren is within 60 ft., her Siren Dirge DC is 16 instead of 15.
Shipboard Presence. Lairs on the fog-skiff (2nd ship) or hangs from the mast if the skiff is destroyed.
Multiattack. Three sting tendrils, or two tendrils and Dirge.
Sting Tendril. +8 to hit, reach 15 ft. Hit: 12 (2d8+3) piercing + 10 (3d6) poison.
Siren Dirge (Recharge 5–6). 60 ft.; each creature of her choice DC 15 Wisdom or charmed+incapacitated 1 min (repeat end of turns). Deafened immune.
Sow Fog-Witches (1/day). Summons 2 Thalassic Jelly-Witches in fog within 30 ft.
Tendril (Cost 1). One sting tendril.
Drift (Cost 1). Fly/swim 20 ft. without provoking.
Call Wings (Cost 2). 2 Harpies within 120 ft. each make one claws attack.
Sea Spirit (Lesser Nereid)
Medium Fey, Chaotic Neutral · CR 1/2 · Mini ×5
AC 12 | HP 22 (5d8) | Speed 30 ft., swim 30 ft.
Optional clutter/allies
Mist Form. Can Hide as bonus action in fog.
RECRUITMENT. Kindness DC 12 Persuasion → one spirit extinguishes a fire on the sail once.
Slap. +4 to hit. Hit: 5 (1d6+2) bludgeoning.
NPC / Item
Thetis-Touched Envoy (Quest Giver)
Medium Fey, Neutral Good · Quest Giver
Public face: salt-robed messenger aboard the mist-trireme
Motivation. A siren-queen is calling ships onto rocks — stop the song before the next convoy dies.
Secret. The song is amplified by jellyfish-fog witches bound to the queen.
Conch of Relative Silence
Wondrous Item (maguffin), Unique
Appearance: pale conch etched with closed lips
Handout (21 words). "When wings blot the sail and the sea begins to sing, breathe this shell — deafness is mercy, and mercy is a blade."
Enc. 1–2. Action: you and allies within 10 ft. auto-succeed saves vs. siren song until end of your next turn (1/short rest).
Enc. 3. Action: shatter the conch’s silence-pulse (once) — all siren/jelly casters DC 15 Con or lose concentration and song for 1 round; deals 20 thunder to the Fog-Mother if she is within 30 ft.
Reward Cards
Post-session keepables. Reward is the first tag. Mechanics below are for ongoing use after this oneshot.
Conch Echo of Relative Silence
Reward · Wondrous · 1/Short Rest
Mechanics. Once per short rest, as an action, you and allies within 10 feet automatically succeed on saving throws against magical song, charm-song, or siren effects until the end of your next turn. Once per long rest, as an action, release a silence-pulse: each creature concentrating on a spell within 30 feet must succeed on a DC 15 Constitution saving throw or lose concentration, and song-based attacks fail until the start of your next turn.
Appearance. A pale conch etched with closed lips, cracked along one spiral but still cold to the ear.
Lore. What remained after Relative Silence spent itself on jelly-crowned song above the wine-dark sea.
Quote. "Deafness is mercy, and mercy is a blade." — Conch of Relative Silence
Earn when: Shatter the Fog-Mother's song; the broken conch leaves a hush that still answers.