Umber Hulk Evolving Monsters: D&D 5e DM Workshop

Umber Hulk featured image is a combination of images credited to Wizards of the Coast’s D&D 5e book Waterdeep: Dungeon of the Mad Mage.
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Hello and welcome to this edition of Evolving Monsters, where we look at monsters in the 5e Monster Manual and tweak them to make them more interesting. Today we’ll be looking at Umber Hulks and how they interact with others in the planes, as well as how they can be a more detailed part of any world lore.

Umber Hulk

The Umber Hulk is another of Flutes‘ favorite monsters that he requested me to cover. At first glance, the Umber Hulk isn’t much beyond a burrowing bug tank. Its confusion ability is interesting, but it needs more. Let’s explore the ecology of the Umber Hulk and how we can use it effectively in our games.

Confusing…

A brute, the very definition of a brute. In terms of the mechanics over the life of Dungeons and Dragons, the Umber Hulk hasn’t changed much at all. As found in the Monster Manual on page 292, the Umber Hulk is a tactically straightforward bag of hit points that deals a decent amount of damage and rarely comes with different encounter variations. As a game master, this monster is pretty vanilla for running in combat, and in 5e, only a threat to the party if they are low on resources or in the middle of low-tier play. With a base challenge rating of 5, the Umber Hulk is a monster that I want to love, with a concept and lore that grabs the imagination. However, their stats only make it something that can be useful for GMs at low-tier play, and then they get left in the dark.

In the texts of the Umber Hulk, ambushing and confusion attacks are the name of the game, but the stats have difficulty living up to those standards. There is no specialty ambush attack or hint at the tactics besides “…burst out from the wall and confuse the enemy…”, this leaves a lot to be desired in the monster stat block itself. Secondly, since this is almost exclusively a solo monster, I’ll need to be creative with how the high-tier encounter is developed.

Being solo hunters and brutes, they’ll need to rely on ambushes and traps. The high intelligence of the Umber Hulk allows for the use of thought-out and effective trap-making using the natural environment as an enhancement to its combat capability. Secondly, they’ll need to have added mechanics for interactions within the environment; they are already on the bad end of the action economy and so will need as much help as they can get. They’ll get this much-needed boost through interaction with the environment.

Damage Immunities and Resistances

An Umber Hulks carapace is specialized to withstand all bludgeoning attacks and can withstand most physical attacks as well. The Umber Hulk is immune to bludgeoning damage from non-magical sources and is resistant to bludgeoning, piercing, and slashing damage even from magic sources.

Tunneller’s Ambush

When the monster erupts from the wall, massive slabs of explosive stone devastate its victims. During the surprise round, the Umber Hulk can use the walls of the cave to enhance its initial attack. Using a bonus action, any creature that is within 10 ft cube of where the Umber Hulk emerges from the wall of the cave must make a Dexterity save or take damage (DC and Damage in Stat Block).

Controlled Cave-in

The monster can bring the walls and ceiling of the cave down onto its prey. The Umber Hulk controls the terrain underground with the ability to use the cave itself as a weapon. Action: As an action, the Umber Hulk can cause a cave-in that will collapse a section of the wall or the ceiling adjacent to it. This will cause a 5 ft by 10 ft area to be filled with debris and rubble 10 ft high; any creature caught in this effect will need to make a Dexterity save or take damage and be buried (Incapacitated). On a successful save, they take half damage and can choose which side to be displaced to (DC and Damage in Stat Block). A buried creature can attempt to escape by making a strength check equal to the save DC at the end of their turn.

Debris Spray

Using its powerful claw, the monster augments its attacks or activates a previously hidden trap. Bonus Action: As a bonus, the Umber Hulk uses its massive claws to either activate an adjacent prepared trap or spray debris and rubble into an enemy before a brutal frontal attack. Debris Spray (Stats for the attack are in the Stat Block) Upon a hit, the Umber Hulk has advantage on melee attacks against the target until the beginning of its next turn.

Traps

An Umber Hulk sets up traps at the ambush site ahead of time to gain the upper hand during combat. An Umber Hulk will set up a series of traps at the ambush site before the combat if it has time, listed below are a few examples. These traps are different from normal traps as the Umber Hulk itself is the triggering mechanism and they cannot be disabled.

Fall Trap

A portion of the ceiling collapses on an area. An area 10 ft by 10 ft has a portion of the ceiling collapses onto it. All creatures in the area need to make a Dexterity save (DC in Stat Block) or be crushed by the falling rock. On a successful save, a creature is moved to the nearest space (if there’s a tie on spaces then the creature chooses) and takes half damage. On a failed save, the creature takes 4d10 bludgeoning damage, is knocked prone, and is restrained (escape DC in Stat Block).

Pit Trap

A section of the floor breaks apart, revealing a pit with jagged rocks at the bottom. A section of the floor (10 ft by 10 ft) breaks apart and a 30-ft-deep pit is revealed. Jagged rocks are piled at the bottom of the pit. All creatures in the area of the trap must make a Dexterity save (DC in Stat Block) or fall into the pit, taking fall damage. On a successful save, a creature is moved to the nearest space (if there’s a tie on spaces then the creature chooses). On a failed save, a creature takes fall damage (3d6 bludgeoning) plus 2d10 piercing damage from the jagged rocks below and falls prone. The pit floor is difficult terrain.

Pit Cap Trap

Making use of multiple traps, this trap slowly crushes its victims. A combination trap, the Pit Cap Trap is a pit trap combined with a fall trap. A large flat piece of the ceiling is released directly above a pit trap crushing everything beneath it. A creature in a pit trap must make a Strength save (DC in Stat Block) or be crushed by a dislodged portion of the ceiling. On a successful save, the creature takes half damage. On a failed save, the creature takes 4d10 bludgeoning plus 2d10 piercing damage and is knocked prone. This save is repeated at the beginning of every turn the creature is being crushed by the stone, and every time a large or larger-sized creature moves on top of the stone. To escape, the creature must use an action to succeed in a strength check (DC in Stat Block) to push the stone far enough to squeeze out of the trap, if the check is successful the creature ends up on top of the stone, stunned until the beginning of its next turn.

Note on Cave-ins

I’m using cave-ins a lot for this monster, I cannot find a good set of rules for dealing with cave-ins, so I’m going to make some up now. For the purposes of this monster, I’m going to use a set of rules that apply only to the cave-ins that it creates. As a StoryCrafter, you may come up with something better. Any cave-in that an Umber Hulk creates can be cleared by doing 10 points of thunder; 20 points of bludgeoning or force; 40 points of slashing, fire, cold, or acid; or 60 points of piercing or lightning damage to it, or any combination thereof. Necrotic, Poison, Psychic, and Radiant damage have no effect. A cave-in wall is automatically hit and only damage needs to be applied from attacks, it is immune to critical hits and fails all saves. Once a cave-in is cleared, the ground that had the cave-in on it is considered difficult terrain.

Endless Mazes of Umber Hulks

An Umber Hulk’s life is one of tunnels, solitude, and hunger. Mages that have been dumb enough to capture an Umber Hulk alive say that the confusion effect is similar to the imprinting of knowledge on a mind, one researcher even says that the confusion effect is the Umber Hulk imprinting the whole complexity of its carved maze to an observer all at once. While the steel-like qualities of an Umber Hulk’s claws can rip through solid stone as if it was loose dirt, the destructive properties of the Umber Hulk are only half of the coin. Glue-like secretions from the mandibles allow the monster to put tunnels back together again to hide its passage, while this can take much time, it is necessary for traps to be adequately designed.

Obscured Origins of Umber Hulks

While they know that Umber Hulks mate, the process has never been directly observed and successfully recorded, divinations suggest a centralized hub or colony similar to a termite mound. However, while all encounters have been solo ambushes in dungeons or caves, there is evidence to suggest that Umber Hulks are social monsters. The intelligence of the Umber Hulk is another clue to a more sophisticated social structure, there are no other intelligent creatures recorded that live a completely isolated life. Coupled with the fact that no Umber Hulk young have been killed or captured up to this point, many scholars believe that there are colonies of Umber Hulks where the young are supported by solo hunters and that most encounters are either the outcasts from the colony or hunters looking for food to maintain the young. The last evidence of an Umber Hulk society comes with the fact that they possess their own language, something that would not be able to develop as isolated hunters.

Backtracking the tunnels to find the origin of any specific Umber Hulk has taken years to explore, even with the assistance of magic. It also typically results in a rapid onset of follow-up attacks from more and more powerful specimens. All expeditions up to this point have ended in total failure. There are rumors of a goblin tribe deep within the wilds of the mountains that has moved into an abandoned Umber Hulk Colony, although one must wonder what would kill an Umber Hulk colony or force it to relocate. On a slightly less comfortable note, it has been noted by more than one adventuring party that Umber Hulks have been thralled by Illithids to be used to carve out hives and access tunnels, as well as bodyguards.

Physiology of the Stone Termite

While alive, an Umber Hulk is a creature of mass and madness. The reinforced carapace is resistant to all forms of physical punishment and resilient enough to have a mountain dropped on top of it and survive. This kind of reinforcement is magical in nature as live specimens have been shown to have a direct connection to the Elemental Plane of Earth. The tunneling ability is unique and many mages have shown that there is a transfer of matter from the material plane to the Elemental Plane of Earth, although the transfer isn’t complete, there is a portion of the excavated matter that is consumed by the Umber Hulk, presumably to maintain its carapace. The thousands of tiny coarse hairs on the exterior of the carapace is what gives the Umber Hulk its tremorsense ability, the tunnels it typically excavates are just barely large enough to fit the monster so that more of the sensory follicles can be in contact with the surface.

The confusion ability as already suggested seems to be imprinting of knowledge from the Umber Hulk to its victim. It is theorized that if a creature had an infinite capability of understanding it would not only be able to avoid the confusion effect but would also be able to map out the entirety of this specific Umber Hulk’s tunnel complex. While this cannot be the case for most sapient creatures out there, there is a select group out there that would seek this out. The severed head of an Umber Hulk retains its ability to cause confusion for months, which could be useful in a variety of applications.

After an Umber Hulk has been defeated, their carapaces are prized for their ability to withstand a lot of punishment, the immunity to bludgeoning damage, and resistance to even magical physical damage make it a prize for armorers and enchanters alike. The carapace itself is prone to accelerated decay once the Umber Hulk is dead and will completely lose its specialized properties within hours if not properly preserved. The eyes of the Umber Hulk are a prized magical component among enchanters as the imprint ability that causes confusion acts as a magnifier for all enchantment magic.

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Umber Hulk Stat Blocks

Tamed Umber Hulk

*Full description found previously in the article

**Full description found in Monster Manual pp 292

This is essentially a copy of the Umber Hulk in the book with the Damage Resistances / Immunities, Controlled Cave-in, Tunneler Ambush, and Debris Spray added in. With the added damage potential and resistances I ended up adding 2 to the CR. This would work as a great thrall or minion added to an encounter of a control-style boss. This stat block assumes that the Umber Hulk doesn’t have the time to set up an ambush or traps.

Horrid Umber Hulk

*Full description found previously in the article

**Full description found in Monster Manual pp 292

Adding save proficiencies, traps, and skills, as well as increasing to hit and damage output on the attacks. While this is a beast of an encounter, a fairly competent mid-tier party should be able to put this monster to rest. The trap abilities in conjunction with the confusion will wreck any mobility that you thought that you had in your melee characters. This is where the support characters really begin to shine as they can lay on the damage at range without that pesky resistance to damage. Using the Controlled Cave-in to isolate from sight the more eager members of the party is a good way for the Umber Hulk to have a great time with fewer distractions.

Truly Horrid Umber Hulk

*Full description found previously in the article

**Full description found in Monster Manual pp 292

***New ability described below

Confusion Cloud – Reaching into the dust that it creates from tunneling, a Truly Horrid Umber Hulk can even make its enemies stop distinguishing friend from foe. A 30 ft aura that surrounds the monstrosity prevents its foes from recognizing allies. Any creature that starts its turn in or comes within 30 ft of the Truly Horrid Umber Hulk must immediately make an Intelligence save (DC in Stat Block) or consider all creatures hostile to it and attack the nearest enemy. If a creature is immune to being frightened or is resistant to fear then they have advantage on the save. Creatures succeeding on their save are immune to the effects of this ability as long as they stay within the aura, if they leave the aura and are affected by it again then they must reroll the save. If a creature takes damage, then they may immediately repeat the save.

In this iteration, we’re not adding a lot in terms of new abilities, but we’re adding in Legendary Actions, and powerful control ability in a new aura, Confusion Cloud (see above). The high DC for the Gaze and Cloud abilities for both Charisma and Intelligence, both of them being minor saves and are typically dump stats, should make the party think twice about tactics when it comes to dealing with this monster, especially when it generally gets to dictate terms on when and where it attacks.

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Umber Hulk Encounters

There are many encounters that a storycrafter could develop to engage your players. The following are just a few examples using the new abilities outlined here.

Added Umber Hulk Minions

With this monster, at least lore-wise, adding them as minions should only really be done when you’re dealing with a boss that can use Dominate Monster or have thralls. With that, I would only use the Tame Umber Hulk as they wouldn’t have the time to set up an ambush if they’re serving a master. Minimize HP to 44 and attempt to use a hasty ambush, interrupting the party in their bid to defeat the boss on round 2 or 3. An Umber Hulk, no matter the HP is something an adventuring party cannot ignore and may give the big bad time to make a getaway.

Ambushed by an Umber Hulk

Unfortunately, all tiers of play have a similar encounter setup due to the fact that the Umber Hulk is typically a solo hunter in caves. Whether the party is out to actively hunt an Umber Hulk or they are just moving through some caves when they get ambushed, the Encounter plays out the same.

Setup

The Umber Hulk will select a narrow cave that acts as a choke point, forcing creatures to move through it. While it is setting up the ambush, if this is a high-traffic area, the Umber Hulk may choose instead to build a bypass so it can ready its traps for use if the combat gets spicy. The choke point may be several hundred feet of a tunnel that it crafts, building its traps in all along the way, winding and weaving paths work best to limit ranged attack effectiveness and line of sight. Typically it’ll opt only to use tunnels that are at most 10 ft wide by 10 ft tall, filling the space and being able to block sight and movement with cave-ins work best to its advantage. Almost every section of the choke point tunnel will be laden with traps. It knows where it will ambush but not where the battle will go from there.

Once an ambush location has been used 2-3 times a Hulk will typically rebuild it if all ambushes have been successful, or move to a new location if the caliber of the enemy is proving more difficult to deal with.

Surprise Round

Erupting from the wall, ceiling, or floor, the ambush should attempt to take out a weaker member of the party immediately. This would be the most lightly armored or lightest, you need to remember it can only “see” via tremorsense so the less noise the more tempting of a target. This is because the creatures that are usually able to deal more effectively with an Umber Hulk are the ones that don’t wear heavy armor and the ones that make the most noise are typically going to be more affected by the Confusing Gaze or Confusion Cloud abilities.

Target the lightly armored first, and attempt to isolate and down someone in the surprise round.

Subsequent Rounds

Isolate the party members that are not affected by the Gaze / Cloud. Use the Controlled Cave-in ability to control where the party can go and target, ensure that the Umber Hulk kills any downed characters as they will be less likely to get back up and start attacking again. All-out attack with Debris Spray to gain advantage on attacks and then wreak havoc with multi-attack. Take advantage of clumping to use either traps or cave-ins to restrict movement and deal a little bit of AoE damage. Take the time to use the traps and ensure that the targeted party member is isolated from support; in this case, it is essential to divide and conquer. The fewer actions the party can take to injure the Umber Hulk directly, the more frightening and longer the combat will last.

If an Umber Hulk is near ¼ hitpoints they will attempt to flee through a soft dirt tunnel that was prepared ahead of time. Use the Controlled Cave-in ability to slow the progress of the party if they would have the idea of pursuing. Umber Hulks don’t hold a grudge as they regard most meat as just another food source. Some food bites back harder than others.

Noncombat

No options, this creature decides to attack when it will. A party might try to parlay during combat, but without magical assistance, it is unlikely to succeed.

Wrap Up on Umber Hulks

A brute, a fine brute. The Umber Hulk is the quintessential monster for raw damage in confined spaces. The confusion abilities add a style that moves away from the typical stand and hit style of monsters. Adding in the abilities that allow the Umber Hulk to manipulate the environment around it and reshape the battlefield in real-time gives it more of a controller monster aspect. Allow the monster to use its intelligence to its advantage, target the low HP low armor cannons, rid the party of annoying combat control characters, block line-of-sight and force the party to think on their feet.

I’ve had fun with this one. I hope you did too.

Until next time

Mike aka RPG StoryCraft