Interesting Combats from Unusual Monster Characteristics

How often do your combats turn out very similar? Attack, batter, dodge, fire bolt, try to flank, bash, slice, (stay in their faces because otherwise opportunity attack), batter, ouch!, heal, crunch, “oh they’re dead”.

Even if you bring in terrain changes and cover to add interest, I’ve still been getting the feeling of things being samey.

However, recently I’ve had several interesting combats caused (mostly) by unusual monster abilities.

Bouncing around

The encounter which inspired this post wasn’t meant to happen at all. One week, several of my players had to pull out at short notice, leaving only two players available. Rather than cancel completely, I dusted off a level 5 encounter from the Kobold Press Tome of Beasts II accompanying Lairs book.

The adventure was “The River Tomb”…and what follows are spoilers, so be warned…

The characters venture into a tomb which has been recently unflooded (is that a word?), and they come into a chamber where there are bubbles floating about. These are Swampgas Bubbles, and they want to consume the exhalations of living creatures. So they try to engulf the characters’ heads and extract the gases…causing the characters to suffocate, but that is not intentional, just a side-effect.

Swampgas Bubble, Tome of Beasts II. Art (c) Kobold Press 2020, used with permission.

Suffocating Grasp. Melee Weapon Attack: +5 to hit, reach 5 ft., one creature. Hit: 6 (1d6 + 3) bludgeoning damage. If the target is Medium or smaller, the swampgas bubble attaches to the target’s head, and the target is blinded while the bubble is attached. While attached, the bubble can’t make pseudopod attacks against the target. At the start of each of the bubble’s turns, the target takes 9 (2d8) poison damage and begins suffocating as it breathes in the poisonous gases within the bubble. A creature is affected even if it holds its breath, but creatures that don’t need to breathe aren’t affected.

A creature, including the target, can take its action to detach the bubble by succeeding on a DC 13 Strength check.

Tome of Beasts II p343

This almost caused the end of our paladin who, despite great Strength, rolled appallingly and failed Strength check after Strength check.

However, that wasn’t the most interesting feature of this creature. This was the one which really made things interesting:

Bludgeoning Bounce. Whenever the swampgas bubble is subjected to bludgeoning damage, it takes no damage and instead is pushed up to 10 feet away from the source of the bludgeoning damage.

It turned out the main melee characters were our Paladin with a war hammer, and a Monk with his unarmed strike/flurry of blows. Note, both bludgeoning damage. So they waded in to the fray, and every time they hit, the bubbles just got bounced away. The only non-bludgeoning weapon the Monk had was his darts, and the Paladin was even worse off, only having spells. (Mind you, mostly the Paladin was busy failing to remove the bubble from his head…).

Fortunately they were not alone. They also had a Warlock, with Eldritch Blast, Sacred Flame and Guiding Bolt (though I did wonder whether the Force damage from Eldritch Blast ought to also send the bubbles bouncing) as well as a dagger, and a Wizard with Fire Bolt and Ray of Frost. But the dice were against them, and these attacks kept missing, and the Paladin was suffocating and the Strength checks (both his and the other characters’) kept failing, and meanwhile these creatures were bouncing about like rubber balls. They do have a bludgeon attack, but that didn’t seem to make thematic sense to me so I just had them trying to engulf all the time.

It certainly made for a memorable encounter. Eventually they managed to free the Paladin and chip away at the bubbles, but it took far longer than would have been expected for three 59hp monsters against four 6th-level characters. It was almost more puzzle than combat.

Chain Reaction

One feature of the Swampgas Bubbles which didn’t actually feature much in this battle was their fire vulnerability and Fiery Death.

Attracted to Fire. A swampgas bubble is instinctively drawn to fire, even though they are highly flammable. Its susceptibility to fire makes it relatively easy to dispatch, but its explosive ending makes the use of fire risky for its foes. In fact, this form of death, accompanied by a beautiful burst of blue light, is just part of the bubble’s overall lifecycle. Its outer layer hardens and shatters, and the remaining bits fall into the swamp where they grow and encase swamp gasses, developing into new swampgas bubbles.

Damage Vulnerabilities fire

Fiery Death. If the swampgas bubble has half its hp or fewer and takes any fire damage, it dies explosively. Each creature within 20 feet of the bubble must make a DC 13 Dexterity saving throw, taking 7 (2d6) fire damage on a failed save, or half as much damage on a successful one.

Note one particular feature of the Fiery Death: “Each creature within 20 feet of the bubble…” This includes other bubbles…who are themselves vulnerable to fire. So if you have several badly hurt bubbles within 20 feet of each other – chain reaction!

I had an interesting encounter during the playtest of the Acid Ant from the Creature Codex by Kobold Press based on that.

Like the Swampgas Bubble, the Acid Ant has an explosive death – in fact it’s even given that name:

Explosive Death. When the ant is reduced to 0 hp, it explodes in a burst of acid. Each creature within 5 feet of the ant must succeed on a DC 11 Dexterity saving throw or take 5 (2d4) acid damage.

Creature Codex p8

When I was playtesting it, I applied this damage to the nearby ants as well, which meant we had a few chain reactions where one ant dying and exploding would cause another to die and explode and possibly cause a third to die and explode. This was quite a fun effect – though it also meant the party had to be particularly careful how they arranged themselves when dispatching an ant because the damage could rack up quite quickly.

Unfortunately, I now realise I missed the following line in the stat block:

Damage Immunities acid

So the explosive death wouldn’t affect the other ants. Oops!

Oh well, it was a play test with one-off characters, and no-one died. The chain reaction was quite cool. Any other creatures which can trigger chain reaction explosive deaths?

Who turned the lights out?

Our party is currently exploring some caverns beneath the city (looking for a dread portal which is allowing demons in), and I was browsing through Keith Amman’s awesome “The Monsters Know What They’re Doing” and came across the Darkmantle. This clings to ceilings, disguised as a stalactite, then drops on passers by below.

I’d already established there were stalactites and stalagmites in this cave system, so it was thematically perfect. And it has a very interesting capability:

Darkmantle (c) WOTC, used under the Fan Content Policy

Darkness Aura (1/Day). A 15-foot radius of magical darkness extends out from the darkmantle, moves with it, and spreads around corners. The darkness lasts as long as the darkmantle maintains concentration, up to 10 minutes (as if concentrating on a spell). Darkvision can’t penetrate this darkness, and no natural light can illuminate it. If any of the darkness overlaps with an area of light created by a spell of 2nd level or lower, the spell creating the light is dispelled.

Monster Manual p46 / Basic Rules

Note in particular that not only does it create darkness, it’s a very effective darkness that defeats Darkvision and dispels spells of 2nd lever or lower. Suddenly the party, who had been blithely going along with their Light cantrips active and Dancing Lights flying about, couldn’t see a thing and were stumbling in the dark. Meanwhile the darkmantle, with its echolocation 60’ Blindsight, could see perfectly well, thank you.

So the party are trying to coordinate by ear, and work out who is where, in a chamber full of stalagmites sticking up in the way, while the darkmantle is happily chewing on Robbie’s Paladin’s head.

(A different instantiation of the Paladin, because the previous campaign died shortly after he introduced the character, but the same player and the same character concept as above. And it turned out this Paladin rolled about as well as the previous one in the Strength saves trying to remove the thing from his head…)

Anyway, it turned out the wizard had been hanging back and was actually outside the 15’ area of effect, so while his Dancing Lights was extinguished by one of them being within the area of effect he was able to re-cast them, and so see where the darkness began, and give some guidance as to distance and how to get out. But the Paladin was now down, and they couldn’t see, and somehow had to work out how to reach and touch him to heal him and attack and remove the darkmantle before it completely killed him.

Another combat which turned into a puzzle, changed things up and added interest.

Lost in the Fog

That turned out so interesting, I decided to double up on the visibility challenges. I introduced an eversmoking bottle to the final cave:

Eversmoking Bottle (c) WOTC, used under the Fan Content Policy

Eversmoking Bottle

Smoke leaks from the lead-stoppered mouth of this brass bottle, which weighs 1 pound. When you use an action to remove the stopper, a cloud of thick smoke pours out in a 60-foot radius from the bottle. The cloud’s area is heavily obscured. Each minute the bottle remains open and within the cloud, the radius increases by 10 feet until it reaches its maximum radius of 120 feet.

The cloud persists as long as the bottle is open. Closing the bottle requires you to speak its command word as an action. Once the bottle is closed, the cloud disperses after 10 minutes. A moderate wind (11 to 20 miles per hour) can also disperse the smoke after 1 minute, and a strong wind (21 or more miles per hour) can do so after 1 round.

A heavily obscured area–such as darkness, opaque fog, or dense foliage–blocks vision entirely. A creature effectively suffers from the blinded condition when trying to see something in that area.

  • A blinded creature can’t see and automatically fails any ability check that requires sight.
  • Attack rolls against the creature have advantage, and the creature’s attack rolls have disadvantage.
Dungeon Masters Guide p168 / Basic Rules

They reached this cavern towards the end of a session, and just had time to fumble into the space, down the 4’ drop that I’d introduced to explain why the creatures inside hadn’t wandered into the rest of the cavern complex (they mostly managed to get down the drop safely by touch…), and then bump into their first monster before it was time to stop.

Fortunate, that. I was coming to realise that maybe this wasn’t such a good idea having everything blinded, and I’d really better have some strategy for how to make it interesting.

So, let’s note some interesting features here.

  • Everyone – characters and monsters – is blinded. That means attack rolls against everyone have advantage, but everyone has disadvantage on attack rolls. Those cancel each other out…and any other source of advantage or disadvantage. So the eerie cackling of the cackling skeletons I had in the cavern, which imposes disadvantage on a failed Wisdom save, get nullified! That’s a shame.
  • They may be blinded, but they can still hear and smell. So if I had introduced a monster which navigates in some other way than vision, like a bat with echolocation, or the darkmantle, they would be unaffected.
  • It takes ten minutes for the fog to disperse after they close the bottle, unless they have access to some way of creating wind (they didn’t).

I took advantage of the two weeks to the next session to really plan out how to make it interesting and workable (and to canvas suggestions from the lovely folk on the SlyFlourish Patreon Discord channel). What I came up with was:

  • Lean heavily on the sound descriptions and following sounds
  • I had already decided there would be Dretches. They have a foetid cloud attack which uses smell, giving another angle of description (in the end I didn’t get a chance to use this!)
  • I found the Cackling Skeleton in Tome of Beasts II which “emits a constant, demoralizing cackle. When a creature that isn’t an undead or a construct starts its turn within 30 feet of the cackling skeleton and can hear the skeleton, it must make a DC 10 Wisdom saving throw or feel demoralized by the skeleton’s cackling. A demoralized creature has disadvantage on attack rolls until the start of its next turn.
  • The description also has: “Nihilistic Hecklers. Cackling skeletons find living creatures’ survival instincts humorous. They find living incredibly futile and believe those that prolong their existence to be hilariously foolish. Unlike other skeletons, cackling skeletons are capable of speech, and they use it to point out the silliness of healing, wearing armour, or other means of self  preservation, often pointing out the creature will inevitably die anyway.
  • These two together gave a nice bit of colour to add while things were happening and an auditory attack that would work through the smoke.
  • I ruled that they could sufficiently see a creature which was right next to them, so the blinded advantage/disadvantage disappeared for melee attacks. Which meant that the cackling skeleton’s Cackle disadvantage could actually have an effect (tee hee hee…)
  • I sometimes allowed ranged attacks to have normal to-hit chance, and sometimes arbitrarily decided they had got the direction wrong when trying to aim by ear
  • I left a bit of parchment with the activation and deactivation words for the eversmoking bottle lying beside the bottle for them to find with the bottle so they could turn it off (though I gave it in a made-up language; they managed to work it out)
  • I set up a trigger, when they stepped on a particular point, to open a portal to another realm in a flash and smell of brimstone, which would
    • Suck all the smoke out of the room so they could see again
Eversmoking bottle instructions

With all of that prep, it did turn into an interesting encounter. We are currently at the point where they have managed to dispatch the dretches and all but one of the cackling skeletons, they have found the eversmoking bottle and closed it, and the final cackling skeleton has led them to step on the trigger, opening the portal, removing the smoke, and turning it into the blazing bones skeleton. The blazing bones skeleton has been turned by the cleric and pinned in a crack in the wall while they have frantically tried to work out how to disable this portal, and a couple of characters have just miscalculated, got out of the cleric’s 30’ range and into the range of the blazing bones, and it has pounced…

However, if you try such a situation, don’t skimp on preparation… I definitely needed the various extra steps to make it interesting, including a way of removing the fog to change it up once it was becoming tedious.

It’s all falling down!

After I posted the above to my amazing patrons who support this blog, and get early access, one of them responded with the following which was so good I had to share it with the rest of you (with permission, of course):

Grick (c) WOTC, used under the Fan Content Policy

I recently adapted a grick nest encounter. The initial encounter was for 4 PCs without magic weapons, and I was adjusting it to make it suitable for five with a few magical gewgaws. I took the four gricks, and made one a Grick alpha, as well as giving it a lair action.

On initiative 20, it would shake the ceiling, causing rubble to fall on any players within the room. A simple effect, with a DEX save. All of this served to make it a much more interesting combat. I had some hairy moments where I was rolling some really good dice, and I worried I’d overdone things, but it made for an exciting, nailbiting fight.

I’d definitely recommend using lair actions as good ways to make an exciting fight, even at lower levels. I’m building a sahuagin boss fight, in which the land under the players feet moves up and down, shifting between deep and shallow water. It’s designed to encourage them to think tactically to defeat the shark folk.

So there are another couple of options for mixing it up.


Battles can become so monotonous and repetitive. The usual recommendations for changing things up are to use terrain features, but interesting and unusual abilities can also make for something different.

What unusual abilities have you used to spice up your encounters?

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