The False Hydra in D&D 5e

What is the False Hydra?

The False Hydra is one of the most famous homebrew monsters created with its original inception coming courtesy of Goblin Punch. A False Hydra is supposedly born of lies, each lie feeding its body until it becomes a terrifying and terrible beast. It is not actually a hydra or a dragon of any kind, though as it matures, it can grow multiple heads. Little is truly known of False Hydras as they are extremely difficult to study (as you’ll soon see).

As it grows, it seeks to feed on the physical rather than the mental and will seek out food where it can find it. This may start as small creatures like worms, but eventually, the False Hydra will sprout from the ground and begin preying on people. This is not too unlike most carnivorous creatures, however, where the False Hydra differs is in its blind song, a song that can rob the hearer of any memory of the False Hydra or its victims! And the False Hydra uses its blind song often, nearly continuously, pausing perhaps only to munch on its next victim.

False Hydra Stats 5e

False Hydra 5e

The False Hydra is a homebrew creation with no official stat block. An official-ish stat block has been created on DM’s Guild here and is used often by DMs.

I’ve updated this stat block somewhat to address some issues with the challenge rating of the creature. In particular, I’ve changed the fact that the hit points don’t really match the creature’s combat damage. In reality though, the main draw of the False Hydra is in its out of combat abilities to create a scary and mysterious adventure.

If you do use the stat block of the False Hydra, it may be worth considering how you scale the challenge rating of the creature. More heads means more attacks and more HP so if you’ve got a large or a tough party, you can give it more heads.

Feel free to also update the damage the creature deals too. It’s also worth considering how you handle chopping off heads. Some DMs will allow players to chop off a head when the False Hydra loses 100hp, others will allow a head to be chopped off when a critical hit occurs. Either way, it’s a good way of demonstrating progress for the players in their goal to kill this abomination. It also makes it a little easier to fight when the party are looking a little more ragged.

  • Large/Huge aberration, Neutral Evil
  • Armour Class: 16 (natural armour)
  • Hit Points: 150 + 100 per additional head
  • Speed: 5ft, Burrow 40ft

16 (+3)10 (+0)16 (+3)12 (+1)20 (+5)20 (+5)

Saving Throws: Wis (+11), Cha (+11)

Condition Immunities: blinded, charmed, deafened, grappled, prone, stunned, knocked unconscious

Senses: Darkvision 120ft., Passive Perception 15

Languages: Understands the languages of its victims

Blind Song: All hostile creatures that can hear the False Hydra sing must make a DC15 Wisdom saving throw at the start of their turn. If the False Hydra sings with more than one head, all hostile creatures must subtract 1d4 from their saving throw. On a failure, the creature forgets the False Hydra is there.

Innate Spell casting: The false hydra’s innate spell casting ability is Charisma (spell save DC 20). It can innately cast the following spells, requiring no components:

At will: detect thoughts

3/day: dominate monster

Legendary resistance (3/day): If the False Hydra fails a saving throw, it can choose to succeed instead.

Multiple Heads: The False Hydra gains an additional action per turn equal to the quantity of heads it has. If the false hydra has 3 heads, it has 3 actions on it’s turn (in addition to move and bonus actions). It does not gain additional move and bonus actions.


Bite: Melee Weapon Attack: +7 to hit, reach 15 ft., one target. Hit: 14 (2d10+3) piercing damage. 

Claws: Melee Weapon Attack: +7 to hit, reach 10 ft., one target. Hit: 12 (2d8+3) slashing damage. If the false hydra succeeds on a claw attack, it can choose to grapple the target instead of dealing damage. (The false hydra can only grapple one creature at a time and cannot use its claw attack while grappling a creature.)

Bonus Action

Sing: The False Hydra can use a bonus action to stop singing or to start its song with an additional head. The False Hydra cannot use its bite attack with a head that is singing.

Regrowth: The False Hydra can use a bonus action to begin regrowing a head that has died. It takes three Regrowth bonus actions to fully regrow a head. It regains 20 hit points each time it uses Regrowth.

Legendary Actions

The false hydra can take 3 legendary actions, choosing from the options below. It can take only one legendary action at a time and only at the end of another creature’s turn. The false hydra regains spent legendary actions at the start of its turn.

Bite: The false hydra makes a bite attack.

Using the False Hydra in an adventure

Setting up the mystery

The fear of the unknown is one of the greatest tools a DM can harness, and this is exactly why the False Hydra has become such a wonderful plot tool. An adventure with a False Hydra should begin as a mystery; strange things going on that can’t be explained until the party are able to piece them all together.

Players might enter a town where too few people live to justify the number of houses. They may sleep in an inn, only to discover the innkeeper is gone, and that they no longer remember the innkeeper at all, but can’t understand how they paid to stay at the inn in the first place.

Men may not be able to understand why they are unmarried, yet have women’s clothes in the house. Women may be confused about the toys they own, despite having no children. Children may be convinced they are orphans, despite living in a well looked after home. Employees may wonder who they’ve been working for and how they’ve been paid without an employer. All these strange clues and hints can begin to form a theory in the minds of the players.

Progressing the plot

An actual hydra, which happens to be quite different from a false hydra

As the players begin to develop their understanding of what’s happening, you may want to develop the clues they’ve been receiving. Perhaps someone had the presence of mind enough to write down what they saw before they forgot it, perhaps even clawed into their own skin. Maybe all the missing people will have gone missing within a certain area helping the players to narrow down their search for the perpetrator.

Whatever the approach, it’s important to have plenty of clues that can help the players along their way so that the adventure doesn’t become stale or grind to a halt as the players can’t work out what to do. An always useful piece of advice for a DM is to recognise that what you know is not what your players know. Clues are only clues and not facts so it’s important to provide lots of opportunities to learn the truth.

Of course, all of this is made the more challenging when the players themselves keep forgetting things due to the False Hydra’s song and its influence on them. It’s important to be clever about how this is used. Wiping the players’ minds just as they get close to discovering the truth and effectively landing them back at square 1 may be frustrating. Instead, it should be used carefully.

Players might work things out and start using memory aids to remind them of what they discover along the way. And if they do pass their wisdom check, don’t worry, there’ll be more in a few turns, but perhaps what they see of the False Hydra is only subtle (at least at first). Perhaps a tail going down a hole or the sound of the blind song itself.

Facing the false hydra

At some point, the players may come up with a solution to deal with the False Hydra. Whilst you do need to stick within the realms of what might work, it is important to reward your players for their creativity and ingenuity. They might decide to plug their ears (or cast deafen on themselves). They might choose to use mirrors to separate themselves directly from what they’ve observed. The might use a spell like true seeing or scrying.

Whatever they do, as long as it makes sense, find ways to allow that to move the plot forward, even if the success is only partial (you scryed something so you know where you need to go, just can’t remember what you’re going there for).

of course, actually defeating the creature is part of the problem too though not an insurmountable one. The greatest part of the false hydra is in the mystery leading to its reveal, but balancing combat is important. If your party is of a low level, feel free to put them against a younger false hydra with reduced stats. If the party are higher level, give the false hydra extra heads to increase its damage output and HP.

You might also want to consider the aftermath of the false hydra’s death. Do the local people suddenly remember everything they’d forgotten once the creature dies? Will some now have nightmares of these now remembered encounters with the false hydra? Will others go into mourning for once forgotten loved ones? Perhaps it may raise the question of whether the people were better off carrying on in ignorance without these sorrows after all and may raise important, moral questions of how much “heroes” truly help.

The False Hydra really is a fun and exciting plot device and one that lends itself well to horror-filled adventures.

Published by DM Ben

Ben is an experienced dungeon master and player who's been immersed in the D&D universe since he was a teenager over 20 years ago. When he's not writing for Dungeon Mister, Ben loves creating fiendish puzzles and devious dungeons for his players. He's an especially big fan of the Ravenloft and Dragonlance settings.

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