Remind me again why we’re on this quest?
-Ethelrede the Fighter, after his first Darkmantle encounter
Farewell, C section! It’s the day of the D now!
The Darkmantle is an odd monster. It has an interesting design and abilities that make for a creative fight. But the lore is so scarce that it may as well not even be there! It is an animal, plain and simple. It isn’t a bad monster, but it is certainly underwhelming.
Lore: They cling to the roof
That’s it. They cling to the roof of caves, living in the Underdark, and wait for their prey. There are only two paragraphs of flavor text here.
This is a fodder monster. You can weave neither a side quest nor a whole campaign around these guys. They exist for one sole purpose: give the party something to fight and kill.
Design: Squid? Octopus? … SQUIDTOPUS!!
How else would you describe this thing? I mean, just look at it!

It is an odd design. On one hand, it is undeniably creative and interesting. There isn’t quite anything like the Darkmantle! On the other, it isn’t the most effective thing in the world.
Taking one look at it, you’d think it’s a monster that lives in the water! The Squidtopus (yes I’m keeping that and I’m keeping it forever) look of the creature immediately make you think “Yup, that lives in the ocean!” But no! It’s actually a cave-dwelling creature! One that sticks to the ceiling and waits for their prey!
It’s a creative design, which does garner a few points on my scale. But it isn’t effective! You can’t glean anything about this thing’s story from its design!
So the lore is underwhelming and the design, while creative, isn’t super effective. It’s all down to the battle! So, how does this thing fight?
Stats: Don’t Kill Your Buddy
In terms of health, armor or damage output, the Darkmantle isn’t much of a threat. The AC is a pitiful 11, the HP is a measly 22(5d6+5), it doesn’t move super far, and it can only deal a maximum of 6(1d6+3) per turn. If it were a more straight-forward monster, like the Cyclops from last week, it would be a complete waste of time.
Except that it’s not. These bastards are tricky!
First: ‘False Appearance’. While this thing is staying still, it is indistinguishable from a stalactite/stalagmite. This is perfect for surprise-attacking the party, which can put them at a challenging disadvantage. Not because it can deal a lot of damage right off the bat, mind you.
Because it can immediately take one member of the party out of the fight!
See, should the Darkmantle successfully land an attack on a creature that is Medium or smaller, it swallows said monster’s head. While in this state, the victim can’t see or breath. Removing the Darkmantle isn’t necessarily hard. But if the one trying to remove it is rolling poorly that particular session? They’re gonna have a bad time.
Also… the other players ought to be careful where they aim their weapons. If they’re not careful, they could do more harm than good.
It also has a special ability: ‘Darkness Aura’. With this, it can create a fifteen-foot radius of magical darkness that not even Darkvision can penetrate. It either requires concentration or simply lasts ten minutes. It can even dispell light-making magic!
Are you tired of your players lording their Darkvision over you? Throw a Darkmantle at them! Put the fuckers in their place!
For higher-level parties, killing the Darkmantle wouldn’t be all that hard. In fact, a third-level Barbarian could probably instantly kill it on a good day! Even lower-level parties wouldn’t have a very hard time! But it does require more creative tactics than ‘HIT IT ‘TILL IT DIES!!”
How will the party deal with being surprise attacked? Will the grappled party member escape before things get really bad? How will the party handle being trapped in complete darkness? Will the Darkmantle (or Darkmantles if you’re really feeling like an asshole) utilize the cover of darkness? How these questions are answered varies from party-to-party, which can make an encounter with the Darkmantle a lot of fun!
Though they could be a bit tedious if you’re not careful.
Conclusion
Does the Darkmantle have interesting lore? Nope. Does it have a good design? Kind of. Does it make for a creative and fun battle? Sure! It is an incredibly mixed bag of a monster!
With all that in mind, let’s put the Darkmantle on the Best of the Bestiary!
- Beholder
- Death Tyrant
- Couatl
- Behir
- Aboleth
- Chuul
- Chimera
- Ankheg
- Aarackockra
- Azer
- Spectator
- Cambion
- Animated Armor
- Banshee
- Basilisk
- Bulette
- Cloaker
- Darkmantle <———
- Planetar
- Carrion Crawler
- Rug of Smothering
- Bugbear Chief
- Bugbear
- Vine Blight
- Twig Blight
- Needle Blight
- Bullywug
- Cockatrice
- Solar
- Deva
- Cyclops
- Centaur
- Flying Sword
- Crawling Claw