We’ve all been there, it’s the middle of the night, you’re just trying to make your way down the hall in the dark when something spooky catches your eye. For just a moment you think you see a figure lurking in the corner, but as soon as you flick on the light, you breathe a sigh of relief at the coat and hat slung over the rack in the corner.

That’s when you remember, you don’t own a coat rack.

Sliding out from the cloak are a series of emaciated arms with sharp, needle-point fingers, and they’re reaching, hungrily, for you. You’re the latest victim of a particularly ghastly foe from Kobold Press’s Tome of Beasts 1, the cambium.

• What Is the Cambium?
• What Makes the Cambium So Scary?
• How Can You Cambium?

Unleash Over 400 Monsters from Kobold Press

Tome of Beasts 1 introduces hundreds of new monsters for use in your home games. When you purchase your copy of the book on D&D Beyond, you'll immediately find the monsters in the compendium and available for use in our encounter builder; combat tracker; and Maps, an official virtual tabletop.

The VTT requires only the DM to have a Master-tier subscription, and it allows you to drop in monster tokens and maps on the fly to make running your sessions faster and easier.

What Is the Cambium?

If you’ve ever wondered what sort of creature a vampire might call a glutton, you’ve found it in this CR 14 Fiend. Not content to merely steal the blood of victims, the cambium seeks out all four humors. This consumption is not simply a mindless feeding frenzy, however. While it really is just a mess of scary arms in a cloak, the cambium is a smart creature, with Intelligence 17 and Wisdom of 16. It knows to take precisely the amounts from its victims that it needs. The cambium also hunts both to feed itself, and to collect the humors to make potions to sell.

What Are the Four Humors?

Ancient Greek physician Hippocrates believed that the four main types of bodily fluids (that he knew about at the time) were connected to people’s temperaments and personalities, as well the four elements of wind, water, fire, and earth. Those fluids were: blood, yellow bile, black bile, and phlegm. Think of it like a Myers-Briggs test but with gunk. Versions of this theory continued into the early 20th century when advances in medical research allowed for a more complex understanding.

What Makes the Cambium So Scary?

What is it about this hovering, literal coat of arms that makes it such a threat? Let’s look at a few of its most challenging traits.

So. Many. Hands.

Because the cambium is a creature ostensibly made of hands, it utilizes those to execute a pretty devastating Multiattack, allowing it to strike up to four times.

For those attacks, it can use its Needle Fingers ability to make a melee weapon attack with a +10 to hit with a 10 ft. reach, or it can use Poison Ray, a ranged spell attack that has a +9 to hit and deals poison damage and poisons its target until the end of its next turn unless it passes a DC 17 Constitution save.

The cambium can also forgo two of these attacks when using its Multiattack and instead cast a spell from a list that includes heal, hold person, and even a single use of plane shift.

A Bad Sense of Humor

As if its Needle Fingers wasn’t menacing enough, once the cambium has struck a creature with that attack, it gains access to its Imbalance Humors ability. With this, it can take a bonus action for up to one minute that allows it to manipulate one of its target’s humors.

Imbalance Humors allows the cambium to impose various status effects, including: making the creature confused as if under the confusion spell; incapacitated; poisoned; or even lose the ability to regain HP until it takes a long rest.

These effects can be resisted or ended with a DC 17 Constitution saving throw.

What’s Your Damage?

What I think is the fiercest threat the cambium has up its many, many sleeves is its other bonus action, Damage Ability. Also tied to any creature within 30 feet that the cambium has hit with Needle Fingers in the last minute, Damage Ability reduces a creature’s Strength, Dexterity, or Constitution score by 1d4 unless it succeeds on a DC 17 Constitution saving throw. This ability score remains reduced until the creature takes a long rest. If the score drops to 0, the creature becomes incapacitated.

There are two big reasons why this is such a threat. First, given that this is such a high CR monster, it’s likely that it will be able to deplete a creature’s ability scores a lot faster than the well of HP that a high level player character might have, meaning a cambium has a much quicker pathway to removing its enemies from the board. Secondly, you may have noticed that a Constitution saving throw is the primary defense against most of its attacks, so a wise cambium would target a creature’s Constitution to impact their ability to defend against it.

How Can You Cambium?

In addition to being such a threat in combat, the cambium is poised to be a true nemesis in your game. Here’s some of the ways we think it can be utilized against your players.

Parasitic Master

While the cambium’s stat block doesn’t include abilities to enthrall player characters, the flavor text in Tome of Beasts 1 does suggest that because the cambium takes only precise amounts of its targets' humors at a time, its depleted victims become dependent on the relief it can offer them as it siphons more and more of their humors.

It eventually discards their victims and flees once it feels it has harvested enough, leaving them to die. Before that happens your players could be tasked with solving a series of missing persons cases that eventually lead them to the den of the cambium, full of its suffering victims. The potential for horrific imagery is ripe.

Master of Disguise

While the cambium’s main form is just a bunch of sharp fingered hands in a billowy cloak, the creature’s spellcasting abilities does also allow it to cast alter self at will. This allows it to frequently change its appearance to play a cat and mouse game and spy on the players during their adventure.

Master of Trade

Since the cambium is established as a purveyor of potions and serums it makes from its victims, a DM could introduce a cambium early in the campaign as simply a merchant known to the players and a regular resource for potions of healing and other similar magical concoctions. The reveal that an eccentric merchant that the players have come to rely on is actually a horrific fiend who is literally harvesting victims is one of those big memorable emotional moments that can truly unsettle your table.

Give Yourself a Hand. Or, Hands.

The imagery of the cambium is already creepy to think about, but the usage of real-world historical medical understandings (and misunderstandings) as the flavor that drives it really elevates it to a special level of fearsome. The way that it uses and then discards its victims harkens back to some of the most chilling vampire stories and even some real world underworld treatment of addicts in centuries past. This is why we think the cambium is one of the creepiest monsters in Tome of Beasts 1.

Riley Silverman (@rileyjsilverman) is a contributing writer to D&D Beyond, Nerdist, and SYFY Wire. She DMs the Theros-set Dice Ex Machina for the Saving Throw Show, and has been a player on the Wizards of the Coast-sponsored The Broken Pact. Riley also played as Braga in the official tabletop adaptation of the Rat Queens comic for HyperRPG, and currently plays as The Doctor on the Doctor Who RPG podcast The Game of Rassilon. She currently lives in Los Angeles.