Skip to content
CharGen Icon
CreatePricing
The Thornwing Mournling, Vaelith the Briar Drake - AI-generated fantasy Monster

The Thornwing Mournling, Vaelith the Briar Drake

Ysara encountered the Thornwing Mournling during her early field research, when it was a wounded juvenile trapped in an abandoned royal warding circle. She secretly nursed it back to health and taught it several human words, but concealed the relationship after discovering that the crown intended to study and weaponize the Star-Seal. The Mournling still remembers Ysara as its protector. It now hunts the royal patrols pursuing it, while also being hunted by the second monster. The third monster treats it as prey, and repeated escapes from that predator have caused the Mournling's body and dreams to mutate under the breach's influence.

Monsters
Large fey · High · Unique

The Thornwing Mournling, Vaelith the Briar Drake

A morally ambiguous fey drake guarding refugees and nesting beasts from the spreading Star-Seal breach while sabotaging royal expeditions.
AC17
HP136/136
CRHigh
Init
STR
DEX
CON
INT
WIS
CHA
ConditionsNone

Combat

AC 17 · HP 136 · High

The Thornwing Mournling, Vaelith the Briar Drake

Large fey (fey dragon), chaotic neutral
Armor Class17, natural armor
Hit Points136 (16d10 + 48)
Speed
40 ft.,
Fly 80 ft.,
Climb 30 ft.
STR
DEX
CON
INT
WIS
CHA
Saving ThrowsDexterityWisdomCharisma
SkillsDeceptionInsightPerceptionStealthSurvival
Damage Resistances
Cold,
Fire,
Lightning,
Psychic,
Bludgeoning, piercing, and slashing damage from nonmagical attacks
Immunities
The frightened condition caused by its own Stolen Voice or Briar Veil,
Magical sleep
Weaknesses
Resonant bells, choral magic, and the Star-Seal's particular tone disrupt its supernatural abilities.
It will endanger itself to protect its young, refugees, or creatures it has personally rescued.
It struggles to resist challenges involving Ysara's memory or accusations that it has betrayed her.
The third monster's breach influence causes pain, erratic visions, and involuntary mutations when it comes near.
Senses
Darkvision 120 ft.,
Truesight 30 ft.,
Passive Perception 18
Languages
Common,
Draconic,
Sylvan,
Telepathy 60 ft. with creatures it has frightened or communicated with through dreams
ChallengeHigh
Proficiency Bonus+4
Spell Save DC16
Spell Attack Bonus+8
Passive Perception18
Briar Ambusher. The Thornwing Mournling has advantage on Dexterity (Stealth) checks made in forests, ruins overgrown with vegetation, or areas of dim light. If it surprises a creature, its first attack against that creature deals an additional 7 () psychic damage.
Thornstride. The Mournling can move through nonmagical plants without being slowed by them and without taking damage from them. Magical plants still affect it normally.
Many Borrowed Voices. The Mournling can mimic any voice it has heard. A creature that hears the imitation can identify it as false with a successful Wisdom (Insight) check.
Fey Resilience. The Mournling has advantage on saving throws against being charmed, and magic cannot put it to sleep.
Breach-Tethered Survival. If the Mournling is reduced to 0 hit points while within 1 mile of the Star-Seal, it instead dissolves into thorn shadows, reappearing with 20 hit points in its lair after days. This trait does not function if the Mournling has been affected by Resonant Disruption within the previous minute.
Riddle of the Rootbound Heart. When a creature within 60 feet speaks a personal secret aloud, the Mournling can form a dream-image revealing a symbolic truth about that secret. This is not mind reading and provides no exact factual details.
Keeper of the Hidden Route. The Mournling knows the hidden route from its lair to the Star-Seal chamber. It can guide up to ten willing creatures through the route in 1 hour, avoiding ordinary patrols and natural hazards.

Spells

Minor Illusion (cantrip, illusion). The Mournling creates a sound or image of a familiar creature or object within range. It often uses this to imitate a patrol command, a child's cry, or Ysara's voice.
Invisibility (level 2, illusion). The Mournling becomes invisible until it attacks, casts a spell, or ends concentration. Its concentration can last up to 1 hour.
Darkness (level 2, evocation). The Mournling creates a 20-foot-radius sphere of magical darkness that it can see through.
Charm Person (level 2, enchantment). The Mournling charms a creature for up to 1 minute if it fails a Wisdom saving throw. The effect ends if the Mournling or its allies harm the target.
Entangle (level 3, conjuration). The Mournling creates a wall of tangled, thorn-covered vegetation in a 20-foot square. The wall provides cover and makes the area difficult terrain.
Misty Step (level 2, conjuration). The Mournling steps into shadow and reappears in an unoccupied space within 60 feet that it can see.

Actions

Multiattack. The Thornwing Mournling makes one Bite attack and one Thorn Talon attack, or it uses Briar Veil and then moves up to half its flying speed without provoking opportunity attacks.
Bite. Melee Weapon Attack: to hit, reach 10 ft., one target. Hit: 11 () piercing damage plus 7 () psychic damage. If the target is frightened, it takes an additional 4 () psychic damage.
Thorn Talon. Melee Weapon Attack: to hit, reach 5 ft., one target. Hit: 9 () slashing damage plus 4 () poison damage. The target must succeed on a Strength saving throw or be restrained by spectral briars until the end of its next turn.
Briarstorm Breath (Recharge 5-6). The Thornwing Mournling exhales a spiral of black thorns in a 30-foot cone. Each creature in that area must make a Dexterity saving throw, taking 27 () piercing damage on a failed save, or half as much damage on a successful one. On a failed save, a creature is also blinded by illusionary leaves until the end of its next turn.
Briar Veil. The Thornwing Mournling creates a 20-foot-radius sphere of whispering briars centered on a point it can see within 90 feet. The area becomes heavily obscured to creatures of its choice until the end of the Mournling's next turn. Creatures entering the area for the first time on a turn or starting their turn there must succeed on a Wisdom saving throw or become frightened until the end of their next turn.
Stolen Voice. The Thornwing Mournling targets one creature it can see within 60 feet. The target must succeed on a Wisdom saving throw or hear the voice of a trusted ally issuing a contradictory command. Until the end of the target's next turn, it cannot take reactions and must subtract from its next attack roll or saving throw. A creature that succeeds is immune to this effect for 24 hours.
Dreamstep (Recharge 4-6). The Thornwing Mournling chooses up to three creatures it can see within 60 feet. Each target must succeed on a Charisma saving throw or be teleported to an unoccupied space within 20 feet of the Mournling and become confused by overlapping dream-images until the end of its next turn. The Mournling can then fly up to half its flying speed.

Reactions

Briar Slip. When the Thornwing Mournling is hit by an attack while within 30 feet of heavy foliage, it reduces the damage by 10 () and moves up to 15 feet without provoking opportunity attacks. It cannot use this reaction while affected by Resonant Disruption.

Legendary Actions

Winged Reposition. The Thornwing Mournling moves up to half its flying speed without provoking opportunity attacks.
Whispered Doubt. One creature within 60 feet must succeed on a Wisdom saving throw or have disadvantage on the next attack roll it makes before the end of its next turn.
Thornwake (costs 2 actions). The Mournling targets a point within 60 feet. Thorny ground erupts in a 10-foot-radius area until the start of its next turn. The area is difficult terrain, and each creature that enters it for the first time on a turn takes 5 () piercing damage.
Echo of Another (costs 3 actions). The Mournling uses Dreamstep if available. Otherwise, it uses Stolen Voice without expending that action's normal recharge limitation.
Role
Ambush controller, guardian, recurring rival, and potential ally
Built for
Four characters of 8th level, or a larger party of 7th level characters

Gear

  • Star-Seal Resonator (Quest item, Priceless)A thumb-sized fragment of crystal that produces the resonant tone capable of disrupting the Mournling's powers. It is usually hidden in a nest or carried by a royal seal-bearer.
  • Confiscated Arcane Supplies (Spell components, 250 gp)A bundle of stolen royal spell components, including silver dust, powdered gemstones, incense, and sealed vials of astral essence.
  • Ysara's Field Journal (Evidence, Priceless)A thorn-wrapped field journal bearing Ysara's old research sigil. Most pages are written in shorthand, but several contain affectionate observations about the Mournling's behavior.
  • Mournling Scales (Alchemical reagent, 150 gp each)Three black-red scales that whisper fragments of voices when held near a breach.

Feats

Ambusher
Aerial Skirmisher
Riddlekeeper
Guardian of the Lost

Notes for the game master

The Thornwing Mournling is designed as a mobile CR 8 solo creature that becomes more dangerous in dense terrain.
Resonant Disruption: If exposed to a bell, chorus, or Star-Seal tone chosen by the GM, the Mournling must succeed on a DC 16 Constitution saving throw or lose its flight, reactions, and illusion abilities until the end of its next turn. On a success, it still has disadvantage on attack rolls until the end of its next turn.
The Mournling can use Stolen Voice and Dreamstep to create nonlethal confusion, making negotiation possible even during combat.
Its young are noncombatants unless directly attacked.

Tactics

  1. Opening

    It observes from concealment, allows a patrol or lesser predator to make first contact, then opens with Briarstorm Breath against clustered enemies. It follows with Briar Veil and a fast attack against the character carrying royal magical supplies.

  2. Mid-fight

    It creates Briar Veils between combatants, attacks isolated targets, uses Stolen Voice against healers and commanders, and dives through thorny terrain before retreating into darkness. It uses its knowledge of the woods to force enemies across unstable ground and breach-tainted clearings.

  3. End of the fight

    It attempts to separate the strongest threat from the rest of the group, then uses Dreamstep and flight to reach a hidden route or its nest. It fights to protect its young or prevent magical supplies from reaching the Star-Seal, not to claim needless kills.

  4. Retreat

    The Thornwing Mournling retreats when reduced below 45 hit points unless its young, Ysara's keepsake, or a Star-Seal fragment is directly threatened. It flees through narrow aerial passages, false trails, and illusionary duplicates, leaving behind thorn snares rather than making a final stand.

How it fights

Begin hidden or invisible whenever possible.
Use terrain and Briar Veil to break line of sight before selecting isolated targets.
Prefer frightening, displacing, or restraining enemies over dealing maximum damage.
Attack magical supplies, spellcasters, and commanders first.
Use flight to cross hazards that ground-based enemies cannot navigate.
Never remain within reach of multiple enemies unless protecting its young.
Use stolen voices to create false orders, fake reinforcements, or emotional hesitation.

Who it attacks first

Creatures carrying royal magical supplies
Spellcasters attempting to control or weaponize the Star-Seal
Any creature threatening its young or protected refugees
The party member most likely to expose the crown's deception

Works well with

Ysara can calm the Mournling by speaking a phrase from her old field journal or displaying her protective sigil.
The second monster can force the Mournling into the open, creating a three-sided encounter involving royal patrols and breach predators.
The third monster's presence causes the Mournling to suffer waking mutations, increasing the danger of any confrontation near its nest.
Resonant bells carried by an allied choir can suppress the Mournling's illusions while allowing the party to pursue a larger breach threat.

How to beat it

Resonant bells, choral magic, and the correct tone from a Star-Seal fragment disrupt its illusions and suppress its flight.
Bright, sustained light limits its use of woodland concealment.
Protecting or evacuating its young can end the battle without defeating it.
Spells and abilities that prevent teleportation or impose silence reduce its mobility and stolen-voice tricks.

Ways to avoid a fight

It can imitate the voice of any creature it has heard for at least 1 minute.
It can transmit brief sensory dream-images to a willing or frightened creature within 60 feet.
It can guide travelers through hidden root tunnels and concealed paths near the Star-Seal.
It can negotiate safe passage in exchange for stolen royal supplies, protection for its young, or a promise concerning the celestial entity.

Ecology

A lean, draconic fey with a wingspan of nearly twenty feet, the Thornwing Mournling has bark-dark scales threaded with living red thorns. Its wings resemble translucent leaves stretched across blackened bone, and pale blue lights drift beneath its scales like trapped stars. Its antlered head bears a narrow crown of ivory spines. When it speaks, its mouth moves with the voice of someone the listener trusts.

Behavior

Suspicious, theatrical, and fiercely protective. It communicates through riddles, stolen voices, brief dream-images, and arrangements of thorn branches. It avoids killing refugees, nesting creatures, and those who show genuine mercy. It views royal patrols as agents of a dangerous lie, though it does not fully understand the crown's plan.

How it lives

The Thornwing Mournling is born where fey draconic blood, old woodland magic, and a wounded celestial boundary overlap. Its young feed on corrupted dreams and mineral-rich magical residue, but prolonged exposure to the breach causes painful mutations. The Mournling hunts breach-twisted predators, shelters displaced villagers, and steals spell components to stabilize its nest.

Lair

Its lair is a hollow observatory grown over with thorn trees, located above a network of root tunnels leading toward the Star-Seal chamber. Refugees hide in camouflaged burrows beneath the observatory, while the Mournling's young sleep in a nest lined with stolen royal banners and Ysara's old protective charms.

Habitat
Blighted forests, ruined borderlands, fey crossings, overgrown observatories, and the outer reaches of the Star-Seal complex.

Signs that it is near

Royal supply crates opened without broken locks
Thorn patterns shaped like warning symbols
Dreams featuring a blue star sinking into black roots
Patrol horses refusing to enter a particular stretch of forest
Faint echoes of familiar voices coming from empty branches

Tags

fey,
dragon,
ambusher,
illusionist,
guardian,
blighted woods,
Star-Seal,
Ysara connection,
potential ally,
recurring antagonist

Lore

Ysara encountered the Thornwing Mournling during her early field research, when it was a wounded juvenile trapped in an abandoned royal warding circle. She secretly nursed it back to health and taught it several human words, but concealed the relationship after discovering that the crown intended to study and weaponize the Star-Seal. The Mournling still remembers Ysara as its protector. It now hunts the royal patrols pursuing it, while also being hunted by the second monster. The third monster treats it as prey, and repeated escapes from that predator have caused the Mournling's body and dreams to mutate under the breach's influence.

What drives it

Protect its young, refugees, and vulnerable woodland creatures; sabotage the crown's attempt to weaponize the Star-Seal; preserve the hidden route to the seal chamber; and determine whether the heroes are worthy of Ysara's trust.

After the fight

If spared, the Thornwing Mournling reveals a hidden route toward the Star-Seal chamber and leaves behind a thorn marked with Ysara's field sigil. If betrayed, it begins stalking the party, stealing voices from their allies and leading them toward increasingly dangerous breach-tainted hunting grounds. If its young are harmed, it abandons diplomacy and becomes a persistent recurring antagonist.

“The Mournling still remembers Ysara as its protector.”
From its lore

Variants

Young Thornwing Mournling: Medium fey dragon, CR 3, 45 hit points, AC 15, fly 60 feet, no legendary actions, and Briarstorm Breath deals 14 (4d6) damage.
Breach-Scarred Vaelith: Increase hit points to 170, add resistance to force damage, and cause Briarstorm Breath to deal force damage instead of piercing damage. The creature becomes less willing to negotiate.
Bellbound Vaelith: The Mournling has willingly accepted a resonant bell collar. It loses Breach-Tethered Survival but gains immunity to effects that would silence or deafen it and can cast Healing Word at will on creatures it considers under its protection.

Hooks

Plot hooks

A royal patrol claims the Mournling is a murderous beast, but refugees describe it as the only creature protecting them from breach-tainted hunters.
Ysara's old notes reveal that she once saved Vaelith and may have known the hidden route into the Star-Seal chamber.
The second monster has placed a bounty on the Mournling and uses royal agents to flush it from its nesting grounds.
The third monster has begun stalking Vaelith, forcing the party to choose whether to help the drake or follow the predator to a deeper breach.
Vaelith knows the crown's public story about the Star-Seal is false, but it needs the party to recover proof from a stolen supply convoy.

How to use it

Use it as a misunderstood guardian during the party's first expedition into the blighted woods.
Make its stolen magical supplies traceable to a royal project attempting to weaponize the celestial entity.
Allow the party to earn its aid by sparing its young, exposing the crown's deception, or promising to prevent the Star-Seal from becoming a weapon.

Treasure

Ysara's field journal and protective sigil
Stolen royal spell components worth 250 gp
Three Mournling scales worth 150 gp each to an alchemist or fey scholar
A Star-Seal resonator that can produce Resonant Disruption once per short rest when properly tuned

Media

0 images

No images yet.

Visual sheet

Turn The Thornwing Mournling, Vaelith the Briar Drake into a sheet

A high-res, share-ready sheet you can post or print.