# The Rot of the Emerald Tyrant
_A Sordia Vignti Adventure_
**Level Range:** 9–12
**Setting:** Baldur's Gate
**Theme:** Siege, investigation, necromantic corruption
**Primary Antagonist:** Vecna-corrupted green dragon
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# Adventure Summary
A corrupted green dragon bearing the mark of **Vecna** has begun launching repeated hit-and-run attacks on Baldur’s Gate. Each assault spreads necrotic corruption across the city and raises the fallen as undead.
The dragon never stays long enough to be defeated. It strikes, devastates a district, and disappears into the wilderness.
The party must defend the city, uncover the creature’s patterns, and locate its lair before the next attack destroys Baldur’s Gate entirely.
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# Adventure Structure
The adventure unfolds across **three acts**.
|Act|Focus|
|---|---|
|I|Dragon attacks the city|
|II|Investigation and defence|
|III|Assault on the dragon’s lair|
The dragon launches **three major attacks** during the adventure.
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# Act I — The First Attack
## Arrival
The party arrives in Baldur’s Gate as chaos erupts.
A terrible roar echoes across the harbour.
The sky turns green with poisonous vapour as the dragon descends.
Read aloud:
_"A massive shape tears through the clouds above the city. Emerald scales streaked with black rot glint in the light of burning rooftops. The dragon exhales a cloud of sickly green mist that spreads across the streets. Where it touches flesh, people collapse… and moments later, they begin to rise again."_
The dragon circles the city once, breathes its corrupted poison across a district, and departs.
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## Street Encounters
While the dragon attacks overhead, the party must deal with chaos on the ground.
Possible encounters:
**Undead outbreak**
Victims of the dragon’s breath rise as zombies.
**Collapsing buildings**
Players must rescue trapped civilians.
**Flaming Fist defence line**
Soldiers struggle to hold a barricade.
Clues discovered after the attack:
- Survivors saw the dragon **flying north-east after the assault**
- Its poison **reanimates the dead**
- Necrotic runes are burned into its scales
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# Act II — The Siege of Baldur’s Gate
Over the next two days the dragon returns repeatedly.
Each attack lasts **10 minutes of in-game time** before it retreats again.
The party must defend the city while investigating where it is coming from.
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## Attack Two — Nightfall
The dragon strikes at night.
It specifically targets **temples and clerics**, destroying divine wards.
Encounters during this attack:
- undead flooding the temple district
- cultists of Vecna assisting the dragon
- a necrotic fog spreading through streets
Clue discovered:
Cultists carry maps marking **a ruined fortress north of the city**.
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## Attack Three — The Dragon Hunts the Party
By the third attack the dragon recognises the heroes.
It focuses its attention on them.
It may:
- drop undead from the sky
- destroy nearby structures
- attempt to isolate the party
When the dragon retreats again, scouts report seeing it land near the **Chionthar cliffs**.
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# Investigation Phase
Between attacks the party can attempt to uncover the dragon’s lair.
Possible methods:
**Tracking the dragon**
Survival checks follow the flight path.
**Studying necrotic residue**
Arcana reveals Vecna corruption.
**Interrogating cultists**
Captured cultists reveal the location of the ritual site controlling the dragon.
Eventually the party learns the truth.
The dragon is being **anchored to the world by a necromantic relic hidden in its lair**.
Destroying the relic will weaken the dragon.
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# The Dragon’s Lair
The lair lies within a ruined fortress hidden in poisoned woodland.
The land itself is corrupted.
Signs of decay appear everywhere:
- trees rotting from the inside
- animals twisted into undead forms
- black fog clinging to the ground
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## Lair Areas
### Outer Woods
Undead beasts patrol the forest.
Possible encounters:
- skeletal wolves
- corrupted treants
- cultist scouts
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### Ruined Fortress Gate
Broken battlements surround the structure.
Ballistae once used to defend the fortress are now controlled by undead soldiers.
Players may:
- fight through
- sabotage the defences
- sneak inside
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### Ritual Chamber
Cultists of Vecna perform a ritual maintaining the dragon’s corruption.
Destroying this ritual weakens the dragon before the final battle.
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# Final Encounter
The dragon returns to defend its lair.
When the party enters the inner courtyard, the corrupted dragon descends.
The creature’s scales are cracked and leaking black necrotic energy.
Halfway through the battle, the corruption intensifies.
The dragon gains additional abilities:
- necrotic breath that raises undead
- summoning skeletal minions
- shadow teleportation
When the dragon dies, its chest splits open.
Inside lies a fragment of dark magic connected to Vecna’s power.
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# Adventure Rewards
Possible rewards include:
- Vecna relic shard
- corrupted dragon scales usable for magical crafting
- treasure from the ruined fortress
The city of Baldur’s Gate offers additional rewards for saving it.
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# Campaign Hooks for Sordia Vignti
This event may tie into larger Vecna plots.
Possibilities:
The dragon was sent as a **warning to the party**.
The relic inside its heart is connected to the **Hand of Vecna** or **Eye of Vecna**.
Destroying the dragon may only delay Vecna’s larger plans.
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# Running the Adventure
To keep tension high:
- let the dragon appear briefly each time
- keep players moving between defence and investigation
- allow them to influence the city’s survival
The party should feel like they **earned the final confrontation**.