Darkmantle — Lurker of the Lightless Ceiling
A cave predator that pretends to be a stalactite, smothers the light and drops directly onto a victim’s head.
The Darkmantle is a small subterranean ambusher with a cone-shaped body, a ring of webbed tentacles and the ability to cling motionless to stone. Hanging from a ceiling, it can pass for an ordinary stalactite until prey walks beneath it. Then the creature drops, wraps itself around the victim’s head and turns the surrounding passage dark.
At a Glance
Run It Tonight
Put the darkmantle where the party has already looked once. An ordinary-looking stalactite hangs over the route back, not the unexplored route ahead. When someone passes beneath it alone, the creature drops, extinguishes vision and turns a simple corridor into a rescue problem.
Rules by Edition
Darkmantle
Small Aberration, Unaligned
AC 11; Initiative +1 (11)
HP 22 (5d6 + 5)
Speed 10 ft., Fly 30 ft.
16 (+3)
12 (+1)
13 (+1)
2 (−4)
10 (+0)
5 (−3)
Skills Stealth +3
Senses Blindsight 60 ft.; Passive Perception 10
Languages None
CR 1/2 (100 XP); PB +2
Traits
False Appearance. While motionless, the darkmantle is indistinguishable from a cave formation such as a stalactite or stalagmite.
Actions
Crush. Melee Attack Roll: +5, reach 5 ft. Hit: 6 (1d6 + 3) Bludgeoning damage, and the darkmantle attaches to the target. If the target is Medium or smaller and the darkmantle had Advantage on the attack roll, the target has the Blinded condition and is suffocating while covered. A creature can take an action to detach it with a successful DC 13 Strength (Athletics) check.
Darkness Aura (1/Day). Magical Darkness fills a 15-foot Emanation originating from the darkmantle. The effect lasts while the darkmantle maintains Concentration, up to 10 minutes. Darkvision can’t penetrate the area and light can’t illuminate it.
Darkmantle
Small monstrosity, unaligned
Armor Class 11
Hit Points 22 (5d6 + 5)
Speed 10 ft., fly 30 ft.
16 (+3)
12 (+1)
13 (+1)
2 (−4)
10 (+0)
5 (−3)
Skills Stealth +3
Senses blindsight 60 ft., passive Perception 10
Languages —
Challenge 1/2 (100 XP)
Traits
Echolocation. The darkmantle can’t use its blindsight while deafened.
False Appearance. While motionless, the darkmantle is indistinguishable from a stalactite, stalagmite or similar cave formation.
Actions
Crush. Melee Weapon Attack: +5 to hit, reach 5 ft., one creature. Hit: 6 (1d6 + 3) bludgeoning damage, and the darkmantle attaches to the target. Against a Medium or smaller creature, an attack made with advantage can engulf the head, blinding and suffocating the target until the darkmantle is detached with a DC 13 Strength check.
Darkness Aura (1/Day). Magical darkness extends 15 feet from the darkmantle and moves with it while it concentrates, up to 10 minutes. Darkvision can’t penetrate this darkness and natural light can’t illuminate it.
Darkmantle CR 1
XP 400
N Small magical beast
Init +6; Senses blindsight 90 ft., darkvision 60 ft., low-light vision; Perception +4
Defense
AC 15, touch 13, flat-footed 13 (+2 Dex, +2 natural, +1 size)
hp 15 (2d10+4)
Fort +5, Ref +3, Will +0
Offense
Speed 20 ft., fly 30 ft. (poor)
Melee slam +3 (1d4 plus grab)
Special Attacks constrict (1d4+4), grab (any size)
Spell-Like Abilities CL 5th; 1/day—darkness
Statistics
Str 11, Dex 15, Con 14, Int 2, Wis 11, Cha 10
Base Atk +2; CMB +1 (+5 grapple); CMD 13 (can’t be tripped)
Feats Improved Initiative
Skills Fly +5, Perception +4, Stealth +10; Racial Modifiers +4 Perception, +4 Stealth
Ecology
Environment any underground
Organization solitary, pair or clutch (3–12)
Treasure none
Darkmantle
Small Magical Beast
Hit Dice 1d10+1 (6 hp)
Initiative +4
Speed 20 ft. (4 squares), fly 30 ft. (poor)
Armor Class 17 (+1 size, +6 natural), touch 11, flat-footed 17
Base Attack/Grapple +1/+0
Attack slam +5 melee (1d4+4)
Special Attacks darkness, improved grab, constrict 1d4+4
Special Qualities blindsight 90 ft., darkvision 60 ft., low-light vision
Saves Fort +3, Ref +2, Will +0
Abilities Str 16, Dex 10, Con 13, Int 2, Wis 10, Cha 10
Skills Hide +10, Listen +5, Spot +5
Feats Improved Initiative
Environment underground
Organization solitary, pair or clutch (3–12)
Challenge Rating 1
Treasure none
Alignment always neutral
Darkness (Su)
Once per day, the darkmantle can create magical darkness centred on itself.
Improved Grab and Constrict (Ex)
A successful slam can start a grapple. Once attached, the darkmantle constricts for 1d4+4 damage.
Behaviour
Darkmantles are patient but simple predators. They spend most of their time attached to stone above a route used by bats, vermin or larger creatures. A failed drop does not make them fight bravely; they fly back toward a ceiling and try to hide again.
Signs Before Initiative
- A “stalactite” appears in a corridor that was smooth on an older map.
- Bones lie directly beneath one point on the ceiling.
- A faint leathery rustle comes from above when torches move.
- Bats avoid a particular cluster of cave formations.
- A sudden patch of magical darkness appears where no spellcaster is visible.
If Violence Starts
The darkmantle chooses one creature and commits to the smothering attack. Darkness makes rescue harder, but the creature itself is not built for prolonged combat. If allies pull it free or wound it badly, it retreats upward.
Counterplay
Look up before entering narrow passages. Blindsight makes ordinary darkness useful to the creature, but effects that deafen it can disrupt echolocation in the 2014 rules. Once attached, Strength and forced movement are often more important than dealing damage immediately.
Because the darkmantle moves with its victim, careless area attacks can hurt the person being smothered as well.
Rapid Adaptation
Darkmantles mature quickly and live only a few years. Isolated populations can therefore diverge rapidly. Aquatic caverns may produce swimmers, volcanic tunnels may favour heat-resistant hides, and unusually deep caves can produce larger specimens. Treat these as environmental variants rather than default powers stacked onto every darkmantle.
Using a Darkmantle in an Encounter
The wrong stalactite. A mapped corridor contains one formation nobody remembers.
The sewer clutch. A city’s maintenance crews vanish beneath a vaulted drain where a clutch has settled.
The dark rescue. One character disappears inside magical darkness while something leathery tightens around their head.
The volcanic strain. Miners discover darkmantles whose hides have adapted to the heat around an old magma vent.
Related Creatures
Compare the Darkmantle with other ceiling and ambush predators such as the Cloaker, Lurker Above and Grick.
Rules Sources and Licensing
The 5.5e/2024 Darkmantle appears in SRD 5.2.1 and the 5e/2014 Darkmantle appears in SRD 5.1; both SRDs are available under Creative Commons Attribution 4.0 International.
The Pathfinder 1e statistics derive from open Pathfinder rules material. The D&D 3.5e Darkmantle is Open Game Content from the Revised d20 System Reference Document.
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