How WOULD you run a False Hydra to maximize fun (including both horror and victory)?

[Segev]

Same DM (good guy, great world, great descriptions, but his actual DM skills/encounter-building/pacing aren't quite there) ran a false hydra. One of the least fun things I've had in a long time. Because the options are
- very explicitly and obviously meta-game in the bad way
- not interact with anything at all.

It's railroading in a can, with a side of "you can break free, but only by doing something that makes no sense in-universe and you only know to do because you've read about these online." Shades of "read the DM's notes"...

False Hydras are...tricky...all around. Really cool concepts. Probably make for great monsters in a work of fiction where the author controls all the information and the characters' reactions. He can write the discovery of what's going on while still allowing the audience to move from sharing the ignorance to experiencing dramatic irony (and related tension) as the audience learns more about what's going on and some of the characters still don't know.

The trouble with any sort of memory-manipulation plot in a TTRPG is that you can't truly control the players' knowledge. In a work of passively-experienced fiction, if an audience member realizes, "Oh, hey, this is a False Hydra plot!" he can still experience all the tension, because he still doesn't know what parts of what he's perceiving are elements that are broken memories rather than reality. It may even be useful to tell much of the story in the form of in-character narrated flashbacks, so that you see the altered memories of the narrators rather than reality.

But in a TTRPG, you can start off by having - for example - gaps in reality that don't make a lot of sense. Heck, the GM can watch for things that are usually player foibles that have to be retconned or hand-waved, such as leaving the cart with supplies unguarded or not keeping track of who was carrying the loot, and elect to fill in forgotten NPCs who HAD been doing those things.

But building the proper sense of things being "off" is tricky, especially when the PCs should "forget" something that the players clearly do remember. At that point, the PC maybe shouldn't know anything's wrong, but the player absolutely does. And now he has to play information control on his own behavior and choices, which is often not fun simply because it's more stress to keep track of. Let alone if he's a player who plays to succeed at things, and now he's having to deliberately make choices that he knows are sub-optimal (or avoid making optimal choices...or metagame to launder the information he has into something his PC can act on), which is often frustrating.

What techniques would you use to control information, set up the properly eerie vibe, and handle the fact that players don't actually forget things just because their PCs are compelled to? How do you help those who do know, OOC, what's going on and how to deal with it to feel like they still can contribute without breaking character or metagaming?

[stoutstien]

I wouldn't bury the lead and have the <insert manipulation/diversion based npc/faction> not be something that is invertly attempting to effect the PCs so they they can actually interact with it.

[JNAProductions]

What is a False Hydra, in this context?

[stoutstien]

What is a False Hydra, in this context?

A plot hooks with HP.

[JNAProductions]

A plot hooks with HP.

That doesn’t explain much.

[stoutstien]

That doesn’t explain much.

Really not much to explain. It's a NPC block that is entirely reliant on the players to play like they don't know their PCs are being manipulated and farmed as cattle by a creature that can do so but also doesn't have the foresight to think past it's next meal.

[Boci]

That doesn’t explain much.

A homebrew monster who can can sing to make it self invisible, typically interpretative to be in a way that pierces all/most ways of overcoming that like sea invisibility, and can eat people deleting them from time. Most guides to use recommend demonstrating the later by introducing an NPC who gets killed by the hydra, then later denying you ever had such an NPC to your players OOC to represent this deletion.

[JNAProductions]

Okay, thanks for the more thorough explanation.

I don’t think I’d use this without getting player buy-in explicitly. Doesn’t seem like it’d go well without that.

[Boci]

Okay, thanks for the more thorough explanation.

I don’t think I’d use this without getting player buy-in explicitly. Doesn’t seem like it’d go well without that.

Yeah, if a DM sprang that on me without warning (and I didn't know what a false hydra was), I might make a subtle point about honesty and lying by declaring every d20 I rolled that night was a 20 before it finished rolling, then snatching it up as soon as it was rolled, and then swearing blindly it was genuinely a 20 until the DM apologised for blatantly lying to us like that without any warning.

[Anymage]

First off, once you get past the part where the false hydra deletes itself and its victims from people's memories, it's just a big monster that wants to eat people. There are like a kajillion ways that such a plot could be derailed even if you don't factor in players having seen a video about it and taken the recommended steps. PCs are known for attacking people eating monsters on sight, and all you need is for a couple of them to have lucky rolls and the thing will watch its HP disappear.

After that, I'm thinking about both times that Moffat era Who decided to play with the "there's a gap in the world where a person should be" theme. The cracks in time are something I could see higher level PCs dealing with; the gaps in the world clue them in that something is wrong, but it's a largely passive threat that can be researched and explored instead of an active threat that will attack you and then ask you to forget how that happened. Plus, as heroes, they can justifiably be less affected and have the disappeared person be uncomfortable both in- and out of character.

The main plot that false hydras make people think of, the silence, are also easier for a couple of reasons. First, their primary drive is not to eat people and consequently there are a lot fewer gaps left in the world. It's likely to want to interact in ways other than attacking, so you can justify PCs having signs of an encounter that the player did not engage in. That way it's more of a mystery that the players can engage with, instead of either metagaming or having to play dumb around a monster with a particularly annoying shtick.

[PhoenixPhyre]

Yeah, if a DM sprang that on me without warning (and I didn't know what a false hydra was), I might make a subtle point about honesty and lying by declaring every d20 I rolled that night was a 20 before it finished rolling, then snatching it up as soon as it was rolled, and then swearing blindly it was genuinely a 20 until the DM apologised for blatantly lying to us like that without any warning.

It's almost worse if you do recognize it as a false hydra. Because you know that there's no real way to interact with it (since you can't detect it by any means whatsoever) unless you metagame. And even if one character realizes it, no one else can.

So basically, it completely removes any possibility of interaction unless you openly and blatantly metagame by acting on information that the player has but the character cannot (by the setup of the situation) and start doing things that make no sense in-character.

It (the version that was run on me) could also one-hit-delete people. So no indication that anything's wrong, just suddenly characters aren't there. So no interaction prompts, no "this thing is attacking you". Just "so and so was never there."

[Boci]

It's almost worse if you do recognize it as a false hydra.

If I recognise it as a false hydra then I can ask the DM to not use the false hydra, or if they rest of the group is okay with it, then I'll just skip the session and come back when the hydra is dealt with.

[kazaryu]

Yeah, if a DM sprang that on me without warning (and I didn't know what a false hydra was), I might make a subtle point about honesty and lying by declaring every d20 I rolled that night was a 20 before it finished rolling, then snatching it up as soon as it was rolled, and then swearing blindly it was genuinely a 20 until the DM apologised for blatantly lying to us like that without any warning.

i mean, if the DM is trying to deny to the players that such and such NPC ever existed, then i'd agree with you that a mistake has already been made. instead of telling the player 'i never had that NPC' it should 100% be 'you don't remember that NPC.' its even possible that with the right group you could use the dissonance between player/character knowledge as a sort of stand in for the in character confusion.

but yeah, overall i think you definitely need the right group, especially since the main horror of a false hydra isn't something the DM has a significant impact on simulating. its almost entirely on the player being able to really immerse themselves in their character.

[PhoenixPhyre]

but yeah, overall i think you definitely need the right group, especially since the main horror of a false hydra isn't something the DM has a significant impact on simulating. its almost entirely on the player being able to really immerse themselves in their character.

Except that the character has no clue. Because their memories are seamlessly edited. So the "horror" isn't IC at all. There's no "where's Johnny" feeling, nothing. Because they just never existed. The horror is entirely on the players' side, because they are the only ones with the gaps, with the discrepancies. Which works beautifully in a non-interactive media, because you can show that and build up to it. Playing through it is wildly annoying, because you know there are discrepancies, why there are discrepancies, and can't do anything about it without blatantly metagaming. It's a hermetically-sealed plot. It's a perfect railroad--smooth walls, nothing to get purchase on. There is only one possibility that isn't pure blatant "read the DM's notes" metagaming.

[Lord Vukodlak]

The False Hydra is much like the Video Game "Dragon's Lair" its much more enjoyable to watch the story then play all the way through it.
All Things DnD has a short campaign log (https://www.youtube.com/watch?v=PG-vKzEi2bU) of the false hydra story.
Actually it has several but this one is only ten minutes and covers some basic "twists"

[verbatim]

I did this in a Halloween oneshot a long time ago, both for atmosphere and because if everything went sideways it wasn't anyone's main character.

The (Level 14) party was trying to clear a Hag coven out of a town that had entrapped them with a blizzard. Every time they got back from dealing with one of the hags people were missing and when they noticed subsequent disappearances I got subsequently more clear that their characters did not remember that person, rather than that the person irl was mistaken. From the initial blog post I incorporated the warning with someone sleeping writing on their hand.

As the Hydra grew each day it gained heads and the heads got stronger, with the intention that a party figuring it out early could stomp it and that a party that just didn't ever put it together's best hope would be to flee the town after everyone keeping the blizzard up was slain or eaten. They figured it out in the penultimate phase.

I forget who or how but once they figured out that blocking your ears worked it became a 3 way boss fight between them, the Hydra, and the Nagpa who was double crossing the coven. At some point (either narratively before the fight or something the players did mid fight, I forget which) the Nagpa ended up hearing the song and ultimately wound up casting Etherealness and fleeing in confusion. 2 of the 5 ended up surviving, it seemed like everyone had a good time and that the 3 PC's who died (right at the very end) didn't seem bummed about it.


I'm planning on using one in a long term Curse of Strahd at the Abbey. My thinking is that the Abbot is a mute lip reader who uses it to get rid of problematic people, but has to walk a tightrope of not letting it get too big. The party, of which one was in the Halloween one shot many moons ago, is unlikely to make it their until next year so I'm planning on spending a lot of time figuring out tells that they could discover and ways to ensure that a TPK is very unlikely to happen/would feel at least somewhat fair if they made enough mistakes and ignored enough obvious tells.

[Mastikator]

Last year during Easter I was in a game where the big bad was a false hydra. None of the players had heard about this yet so the DM didn't need us not to metagame too much because we had no way of knowing that plugging your ears was the cheat code.

We arrived in a mining town, half the people were gone, ostensibly the mines had run dry and people moved out. The first thing we noticed was a hammer falling from the sky. I went to investigate with my divine soul sorcerer (level 15, so flying) and the DM immediately asked if I was going alone, not even hiding his evil grin. Another player immediately recognized that was a bad idea and went with me (meta-gaming to save my character from death). But there were no added clues, no NPC had anything interesting to say, obviously. The local noble landowner and his entire family and staff was missing too with no explanation but nobody in town thought it was weird. We did a side quest related to a temple turned into a brothel (one of the players was a paladin of said temple's deity), then we mostly wandered the town, explored various stuff like the noble's mansion, taverns, the old mines etc.

Each time we got close to some kind of clue or to the actual false hydra the DM just announced "you all go back to your hotel, rest and gain a long rest, it is now the morning of the next day". Which may seem railroad-y but honestly I don't think it is, the DM knows stuff that the players are not privy to. "That's not what my character would do in that situation" doesn't really apply because the players don't actually know the situation.

The main clue we did get was the name and face of an NPC, Jaden, who apparently had traveled with us. Except none of the players had ever heard of that NPC. This played really well into the whole "people don't just disappear, you forget them".

In the end one of the gifts from Jaden was a potion that made my character immune to the false hydra's song so my character was able to remember everything, he instructed the other characters to plug their ears and then it was showtime.

-

I think- when you have players who know about the false hydra you need a red herring, some side-BBEG who distracts the players while the false hydra is deleting randos at will. Important NPCs go missing at random and the DM will have to tell the players that they don't remember that NPC. When the players figure it out you'll have to remind them not to metagame

[Unoriginal]

I would call it a Stygian Hydra and make so it only affect memories, not anytjing else.

I would say it is connected to the Styx, and can use the planar river's memory-affecting powers in a lesser form, by having a Stygian water breath weapon. Or rather, Stygian vapor breath weapon.

Other than that it would leave all the traces and tracks a huge monster prancing around would leave.

Meaning that the PCs could come across a town where walls and roofs and roads were mangled by the Stygian Hydra, with devoured cattle and several people missing or presumed dead due to blood stains in their last known locations, but no one remembers anything about the monster attacking.

Particularly unsettling if it's been happening over a period of several days, with the monster getting more and more bold, having started from the outskirt farms and people in the woods and is getting closer and closer to the town center.

You can also have things like one of the guards actually managed to hurt it so the guard got slapped into a wall hard enough to kill them rather than eaten, leading to the memory-whiped town people to suddenly notice their splattered corpse once the Hydra left.

Also I would describe the Hydra as having Stygian blue (https://en.wikipedia.org/wiki/Impossible_color) scales, because that's too fun to pass up.

It's still an horror-fuel monster, but in a way that allows agency and satisfying victory.

[GloatingSwine]

I think- when you have players who know about the false hydra you need a red herring, some side-BBEG who distracts the players while the false hydra is deleting randos at will. Important NPCs go missing at random and the DM will have to tell the players that they don't remember that NPC. When the players figure it out you'll have to remind them not to metagame

See there's the problem bit.

If the players played that "in character" without using the meta knowledge that they should remember the NPC they'd have no reason to interact with the plot hook. If they play that "straight" the side BBEG is the BBEG and the false hydra is a giant space flea from nowhere because they shouldn't even try and look for it until it drops on them.

So you have to start with the dichotomy of NPCs not remembering something they should remember in order to give them a reason to investigate without having to use meta knowledge to even start the plot.

The other thing is that once they encounter the beastie for real and start rolling saves it's probably on a pretty short timer before annoyance overcomes horror as they keep losing their chance at walloping it. Nothing destroys a horror experience faster than being annoyed.

[stoutstien]

If a NPC, challenge, or encounter can be easily bypassed by metagaming then it probably shouldn't have been used in the first place.

[Mastikator]

See there's the problem bit.

If the players played that "in character" without using the meta knowledge that they should remember the NPC they'd have no reason to interact with the plot hook. If they play that "straight" the side BBEG is the BBEG and the false hydra is a giant space flea from nowhere because they shouldn't even try and look for it until it drops on them.

So you have to start with the dichotomy of NPCs not remembering something they should remember in order to give them a reason to investigate without having to use meta knowledge to even start the plot.

The other thing is that once they encounter the beastie for real and start rolling saves it's probably on a pretty short timer before annoyance overcomes horror as they keep losing their chance at walloping it. Nothing destroys a horror experience faster than being annoyed.

I think once they discover the false hydra it's time to do or die. The party either act on the knowledge immediately and kill it, or they TPK along with the town, the side BBEG and everything else, the game is over, the end.

In horror movies/shows/books it's not uncommon for the bad guy to win, should be the same for a horror game. A horror game where all the player characters face total defeat and die is still a valid and fun horror game. In power fantasy the good guys (AKA the players) always win, but not in horror.

I think if your players can't enjoy a game where they totally lose, then your players are incapable of enjoying a good horror game. A good horror game would be wasted on such players. Horror games are not for everyone, and that's OK.

[GloatingSwine]

In horror movies/shows/books it's not uncommon for the bad guy to win, should be the same for a horror game. A horror game where all the player characters face total defeat and die is still a valid and fun horror game. In power fantasy the good guys (AKA the players) always win, but not in horror.

Fighting a false hydra and losing is likely to fall out of being a horror experience because you'll be too busy being annoyed at the staccato nature of being allowed to do anything to it (unless you figure out the trick).

It can be horror until it appears, but once it appears it's a beastie with an annoying trick.

RPGs that are good at delivering horror tend more towards horizontal progression skill systems where characters broaden more than they get bigger numbers and there's less focus on combat for reasons.

[stoutstien]

I think once they discover the false hydra it's time to do or die. The party either act on the knowledge immediately and kill it, or they TPK along with the town, the side BBEG and everything else, the game is over, the end.

In horror movies/shows/books it's not uncommon for the bad guy to win, should be the same for a horror game. A horror game where all the player characters face total defeat and die is still a valid and fun horror game. In power fantasy the good guys (AKA the players) always win, but not in horror.

I think if your players can't enjoy a game where they totally lose, then your players are incapable of enjoying a good horror game. A good horror game would be wasted on such players. Horror games are not for everyone, and that's OK.

The problem is the only reason the players can lose is for them to no react at a player level. It's either a "got you" or "hey that's unfair you're metagaming" there is no horror element here because they can't interact with it fairly within in the usual terms that TTRPGs work off of.

To have horror you need unknown elements at all levels of play not just the character's level.

[Chronos]

So, if you don't metagame at all, then when the DM says "You don't remember such-and-such", you behave as if you don't remember such-and-such, and so don't do anything about the monster, until eventually the DM says "Rocks fall, everyone dies, end of adventure".

And if you metagame too much, then you recognize what's going on, and know exactly what steps to take to counter it, and trivialize the encounter.

So this thing only works at all if you metagame just the right amount, not too much, not too little.

Yeah, that has no business existing in the game.

[GooeyChewie]

Split the party. I know, I know, it's a cardinal sin of D&D. But I ran a False Hydra style adventure once and splitting the party actually helped out big time. (I say "style" because I actually used an Elder Brain who abducted citizens rather than a hydra-like creature who eats them, but retained the "erased from everybody's mind" thing.) Here's how mine went:

The adventure begins with the party waking up in an inn, where they had booked one more room than they actually needed. The extra room peaked their curiosity, especially when they went in and found gear that looked suitable for a Paladin. (Note: I chose Paladin because there was no Paladin in the party.) The players did not know it at this point, but they had one more party member when they checked in, who had fallen victim to the elder brain.

After checking out the room, the party went downstairs to get breakfast from the couple who owns the inn. While eating, they are approached by the mayor, who asks their help. The mayor requests that half the party come with him to the sheriff's office, while the other half investigates some mysterious fissures which appeared on a mountain just outside of town. The mayor presented that portion as a pure scouting missions, out of character letting the players know that it would not involve combat so the party wouldn't be split for long.

We played the in-town portion first. The party members got to the sheriff's office, where both the mayor and deputy confirm that they have no sheriff. There's an actual office with "Sheriff" on the door, but nobody uses it. One player promptly applied for the position. Then they did a little digging and figured out that the population of the town was way smaller than expected for the size of the town. At that point, we cut back to the other half.

The other half of the party reached the fissures with no incidents. They searched the area and found some interesting items - a sheriff's badge, a hand-crossbow in a holster, etc.. Basically, physical proof that the town has a sheriff and that sheriff had been taken around here. They also heard distant wailing when they listened at the fissures. At this point, this half of the party came back to rejoin the other half.

The two halves of the party met back up at the inn, now staffed solely by the wife. At this point they have enough information to compare notes and realize something is off. It's also at this point that I revealed a bit of a meta knowledge. I told the half who stayed in town that they don't remember the innkeeper having a husband, and the half who left town that the mayor had most definitely mentioned the sheriff by name before they left town. The forgetting effect had occurred while half the party was out of range. Splitting the party set up a scenario where players did have meta knowledge, but half the party had that knowledge in-character. They were able to use the combined knowledge to figure out what was happening.

At that point they deduced the fissures led to tunnels that led back towards town, and went in and beat up the elder brain and some of its thralls. As soon as the elder brain died, everybody remembered everything, including the Paladin party member who went missing prior to the adventure.


tl;dr Split the party just long enough that some of them forget somebody that others remember, so that there's an in-character reason for the party to have the meta knowledge.

[stoutstien]

So, if you don't metagame at all, then when the DM says "You don't remember such-and-such", you behave as if you don't remember such-and-such, and so don't do anything about the monster, until eventually the DM says "Rocks fall, everyone dies, end of adventure".

And if you metagame too much, then you recognize what's going on, and know exactly what steps to take to counter it, and trivialize the encounter.

So this thing only works at all if you metagame just the right amount, not too much, not too little.

Yeah, that has no business existing in the game.
It just needs:

-A CR/HD cap and an immunity after you pass the save once every 24 hr on the song so it has a reason not to spam it.

-an ability array that makes sense. For A creature that is reliant on misdirection why does it fight like a dumb sack of HP. A very large sack HP.

- a physical shape that mirrors it's burrowing forward movement. Attacks need to mirror this as well

- some sort of motivation past "I eat stuff"

So if you are willing to completely rewrite it you can make it into a functional npc.

[KorvinStarmast]

If I recognise it as a false hydra then I can ask the DM to not use the false hydra, or if they rest of the group is okay with it, then I'll just skip the session and come back when the hydra is dealt with. That's my take on it, generally. I have a hard enough time getting players to remember stuff in our campaign as it is. To declare "you don't remember that" as a meta style is the kind of game I have no interest in playing.

The False Hydra is much like the Video Game "Dragon's Lair" its much more enjoyable to watch the story then play all the way through it. Some things that make a good story or movie don't make for a good TTRPG.

If a NPC, challenge, or encounter can be easily bypassed by metagaming then it probably shouldn't have been used in the first place. I tend to agree. But I guess some groups like this kind of set up. Good on 'em.

So, if you don't metagame at all, then when the DM says "You don't remember such-and-such", you behave as if you don't remember such-and-such, and so don't do anything about the monster, until eventually the DM says "Rocks fall, everyone dies, end of adventure". Which requires meta gaming.
Yeah, that has no business existing in the game. I agree, or, at least in any game I am going to play.

[Mastikator]

The problem is the only reason the players can lose is for them to no react at a player level. It's either a "got you" or "hey that's unfair you're metagaming" there is no horror element here because they can't interact with it fairly within in the usual terms that TTRPGs work off of.

To have horror you need unknown elements at all levels of play not just the character's level.

The red herring's purpose is to trick the players into thinking that there's no false hydra. The players should realize that it's a false hydra from the clues that they need to become deaf, IE they either act on this information immediately and become deaf, or they get eaten and the game is over. That time period where they want to metagame but can't shouldn't exist at all. "Why is there text on my arm saying I need to put cotton into my ears... OOOHHHHH" is the time they need to realize.
The strange occurrences that were previously chalked up the red herring become apparent that they were the result of the false hydra.

If the players start to suspect and voice those suspicions to the other players then the jig is up and then they need in-character reasons to plug their ears ASAP. The tricky part for the DM is to keep the players in the dark as long as possible.

When I played with a false hydra the game was a one-shot, I think a one-shot is how long the DM can keep the ruse up. A false hydra is not something you can build a campaign around.

[stoutstien]

The red herring's purpose is to trick the players into thinking that there's no false hydra. The players should realize that it's a false hydra from the clues that they need to become deaf, IE they either act on this information immediately and become deaf, or they get eaten and the game is over. That time period where they want to metagame but can't shouldn't exist at all. "Why is there text on my arm saying I need to put cotton into my ears... OOOHHHHH" is the time they need to realize.
The strange occurrences that were previously chalked up the red herring become apparent that they were the result of the false hydra.

If the players start to suspect and voice those suspicions to the other players then the jig is up and then they need in-character reasons to plug their ears ASAP. The tricky part for the DM is to keep the players in the dark as long as possible.

When I played with a false hydra the game was a one-shot, I think a one-shot is how long the DM can keep the ruse up. A false hydra is not something you can build a campaign around.

So two sperate "got ya" instead of one? Once you start making wisdom saves the meta gaming is starting. Especially if the party starts asking questions about it because they have features that interact with certain forms of saves but not others. Is It magical? A charm? Mind control? Did I fail it and can I use a reroll feature? Is my X tag along or minion effected? If I'm attacked by something that I forget is there can I still use reaction based on hostile activity?

This isn't a false hydra issue alone. There are plenty of NPCs in the MM that have the same issue like the Limia. Player agency is a hard thing to remove and still have any tension remaining.

[Mastikator]

So two sperate "got ya" instead of one? Once you start making wisdom saves the meta gaming is starting. Especially if the party starts asking questions about it because they have features that interact with certain forms of saves but not others. Is It magical? A charm? Mind control? Did I fail it and can I use a reroll feature? Is my X tag along or minion effected? If I'm attacked by something that I forget is there can I still use reaction based on hostile activity?

This isn't a false hydra issue alone. There are plenty of NPCs in the MM that have the same issue like the Limia. Player agency is a hard thing to remove and still have any tension remaining.

AFAIK the false hydra doesn't impose any saving throws. While you hear the song you are under its effect and nothing is immune to that effect. When the players enter the town they enter its effect and they (and everybody else, including the red herring BBEG) don't suspect foul play. They see vacant houses and when they ask they are told the red herring has been kidnapping people. Everything the false hydra does is attributed to the red herring. As they go about their normal quest to defeat the red herring they stumble upon inconsistencies. NPCs that they spoke to are not there and not even mentioned. The first time they went to the market there were ten smiths and three alchemists, the next time there are seven smiths, the others? What others? The players get suspicious and the DM cuts the day short. "you all go back to your beds and go to sleep". The next time they wake up they have writings on their arms with names they don't recognize, events that never happened, instructions to cast silence or plug their ears.

"Uh that's not what my character would do" a player interrupts the DM. The DM tells them "that's what you remembered happened, and yes, even your character feels their memories are out of character". This should all be contained in a one-shot. Like others have said a false hydra is not campaign material, but it is one-shot material. (and even then, not for everyone)

It's also probably impossible for a group to run a false hydra a second time. You can be in a false hydra one-shot with a new group, or if one or two players have read about the false hydra from the internet before (but preferably not recently). It works best when the players have never heard of the false hydra.

[Boci]

AFAIK the false hydra doesn't impose any saving throws. While you hear the song you are under its effect and nothing is immune to that effect. When the players enter the town they enter its effect and they (and everybody else, including the red herring BBEG) don't suspect foul play. They see vacant houses and when they ask they are told the red herring has been kidnapping people. Everything the false hydra does is attributed to the red herring. As they go about their normal quest to defeat the red herring they stumble upon inconsistencies. NPCs that they spoke to are not there and not even mentioned. The first time they went to the market there were ten smiths and three alchemists, the next time there are seven smiths, the others? What others? The players get suspicious and the DM cuts the day short. "you all go back to your beds and go to sleep". The next time they wake up they have writings on their arms with names they don't recognize, events that never happened, instructions to cast silence or plug their ears.

"Uh that's not what my character would do" a player interrupts the DM. The DM tells them "that's what you remembered happened, and yes, even your character feels their memories are out of character". This should all be contained in a one-shot. Like others have said a false hydra is not campaign material, but it is one-shot material. (and even then, not for everyone)

It's also probably impossible for a group to run a false hydra a second time. You can be in a false hydra one-shot with a new group, or if one or two players have read about the false hydra from the internet before (but preferably not recently). It works best when the players have never heard of the false hydra.

But if the false hydra deletes people, why would the villagers call it a kidnapping? That implies they are still remembered, and missing. Did I miss something?

[GloatingSwine]

AFAIK the false hydra doesn't impose any saving throws. While you hear the song you are under its effect and nothing is immune to that effect.

It's homebrew so there might be variations but the version I've seen in a couple of places is DC15 Wis and it can impose a 1d4 penalty by singing with more than one head.

[kazaryu]

Except that the character has no clue. Because their memories are seamlessly edited. So the "horror" isn't IC at all. There's no "where's Johnny" feeling, nothing. Because they just never existed. The horror is entirely on the players' side, because they are the only ones with the gaps, with the discrepancies. im...not sure what you think you're contradicting in what i said...i said that the main horror of a false hydra isn't something that the DM has any real control over...because it all on the player side....which you contradicted by pointing out that...its all on the player side? im honestly confused.

maybe we disagree on what the horror of the false hydra is? you seem to believe that the horror is meant to kick in when the players notice something wrong, like when the players notice things aren't adding up even when the characters are oblivious. but that isn't how i see it, i don't believe that thats how most horror stories work even in non-active media. I think the horror starts when the characters learn whats happening and have to start contending with questions like 'did we bring an extra horse because we wanted extra space for storage, or was there another member of our group that we don't remember'. thats how it works in things like books and TV shows. you have a character that the reader/viewer is invested in. and *then* all kinds of crazy **** starts happening to them, and since you're invested, you start to feel the fear and apprehension that the character is feeling.

to put it another way, the gaps and discrepancies don't create horror, they don't create fear, not by themselves. what they *do* create is interest. gaps and discrepancies like that are bread and butter for several types of adventures. you throw out several mysterious questions that the players (hopefully) want to answer. Thats pretty standard. in order for it to evoke feelings of horror, you need to give the player a reason to react negatively, and viscerally. in fear, or disgust. and that tends to only happen when they are in a characters head...otherwise what does the player have to fear?

so what i was saying is that the DM can't really control how invested a player is in their characters emotions. and if the player isn't invested in their characters emotions...you can't really run any kind of 'horror' game. horror themed, yes. but if you want to evoke the actual feeling of a horror story, you need that investment. Hence, its all player side. not DM.

does that make more sense?

[Segev]

[A false hydra is] A homebrew monster who can can sing to make it self invisible, typically interpretative to be in a way that pierces all/most ways of overcoming that like sea invisibility, and can eat people deleting them from time. Most guides to use recommend demonstrating the later by introducing an NPC who gets killed by the hydra, then later denying you ever had such an NPC to your players OOC to represent this deletion.Personally, I think a better way to do it is to carefully plan the disappearances such that you can, as DM, present the scenes without the NPCs who will disappear being there, but with events happening that make it clear somebody had to have been there to make them happen. This may work better if you can arrange to start "en medias res" and then run a flashback scene where the PCs are recounting events to somebody...and you do the playing out of those events as part of the recounting.


I would call it a Stygian Hydra and make so it only affect memories, not anytjing else.

I would say it is connected to the Styx, and can use the planar river's memory-affecting powers in a lesser form, by having a Stygian water breath weapon. Or rather, Stygian vapor breath weapon.

Other than that it would leave all the traces and tracks a huge monster prancing around would leave.

Meaning that the PCs could come across a town where walls and roofs and roads were mangled by the Stygian Hydra, with devoured cattle and several people missing or presumed dead due to blood stains in their last known locations, but no one remembers anything about the monster attacking.

Particularly unsettling if it's been happening over a period of several days, with the monster getting more and more bold, having started from the outskirt farms and people in the woods and is getting closer and closer to the town center.

You can also have things like one of the guards actually managed to hurt it so the guard got slapped into a wall hard enough to kill them rather than eaten, leading to the memory-whiped town people to suddenly notice their splattered corpse once the Hydra left.

Also I would describe the Hydra as having Stygian blue (https://en.wikipedia.org/wiki/Impossible_color) scales, because that's too fun to pass up.

It's still an horror-fuel monster, but in a way that allows agency and satisfying victory.This seems like good advice; I particularly like the rename.


tl;dr Split the party just long enough that some of them forget somebody that others remember, so that there's an in-character reason for the party to have the meta knowledge.That does seem like a clever way to do it. If there's a way to handle it so that you can keep the information aligned to the players whose characters would have it, so much the better. Maybe starting with the party having split up, using "en medias res" as an excuse, so you can have them replay the inn and the split as flashbacks as they tell the stories to each other? I don't know how well that would work, but it might be interesting.

[GloatingSwine]

But if the false hydra deletes people, why would the villagers call it a kidnapping? That implies they are still remembered, and missing. Did I miss something?

Yeah, that's another of those things where almost all framings of this sort of adventure will require the rules to be broken for the players so that they know there is something wrong when their characters, by the proper functioning of the monster, could not.

For instance going to the market and there were 10 smiths yesterday and 7 today, no, there weren't.

There were 7 yesterday as well. The characters clearly remember that, they don't remember there being 10. Can't you even count? There were 5 of them yesterday just like there is today.

The number of ways you can include the characters in an effect like this without a discontinuity between them and the players is pretty small, and once that discontinuity exists it's pretty much bound to be the focus of the players' interaction with the scenario.

[Silly Name]

Ever since I first read the False Hydra blogpost years ago, I felt firmly in the camp of "this is a cool horror story, but an awful D&D adventure". If you run it "correctly", for the PCs it basically feels like you have ended up in a town full of paranoid amnesiacs, with metagame knowledge that something is wrong, but also being forbidden from actually interacting with the wrongness unless you start coming up with incredibly convoluted methods, and even then it felt incredibly cheap to me how the original blog post suggested that if the PCs managed to wound the false hydra they would become immune to its song for a limited time - why? How?

It's clearly the only way to let players eventually interact with the monster before it turns into a city-sized abomination, but it's just cheap and anticlimactic. The PCs didn't figure out that the false hydra was singing a song of forgetfulness and took adequate countermeasures - because they are not allowed to - they just started shooting arrows around until one accidentally struck the monster, which they only know exists because the DM has to give them hints in the form of dissociated behaviour and messages to themselves that they didn't actually write.

I don't know, maybe with the right group it could be a fun adventure, one centered around giving up control of your PCs and having to metagame heavily, it could work. But in general I feel like that it either ends up being a "guess what methods the DM has decided are going to let you detect the false hydra because you read the blog post too", which is eminently unfun, or "I have no idea what's going on and this is just a frustrating experience for everyone, can we please go back to actually playing D&D instead of mind-games?".

So, how to answer the thread title? My answer is simply "I wouldn't. Run something actually designed to work within the system you're playing."

[Theodoxus]

I deal with enough gaslighting in my real world life, I certainly wouldn't put it a game, and as soon as I realized the DM was trying to gaslight me saying that some NPC never existed, and I'm crazy for bringing it up, is where I lost my shizzle and delete the DM (figuratively, of course).

From the other threads discussion, I thought a False Hydra was just a name for trying to reskin a more common monster to remove some of the meta data from players so they approach the otherwise common critter with newbie caution and exuberance. Honestly, that would be a far more useful time spent that quarreling over this literary monstrosity that has zero place in a communal game.

[Lord Arkon]

I'm actually considering this in the unspecified future for a solo horror fantasy game I run (not D&D). The Player doubled up on a magic resistance power, so I feel completely justified in declaring them immune to any magic effect if it helps the story. So I would run it with the PC completely immune to the memory loss.

They are sent to town because someone outside of town has hired their detective agency to investigate a relative that suddenly cut contact (this is set in the 1890s). They arrive and hear some weird melody in the wind, no one else from their train hears it. No one knows the missing person, and no one remembers anyone living at the given address. If they check, they find the house is furnished, with spoiled food. Other oddness gets noticed.

After awhile, the singing stops. All the townsfolk suddenly either panic or start crying for lost loved ones, then the singing starts again. Once the singing resumes, no one remembers their panic, also someone the PC talked to is gone and forgotten. Now the hunt is on, and the PC must solve the case, because no one else can. That's why they get the weird jobs.


So... my answer would be find an excuse for the PCs to remember everything.

[Veldrenor]

But building the proper sense of things being "off" is tricky, especially when the PCs should "forget" something that the players clearly do remember. At that point, the PC maybe shouldn't know anything's wrong, but the player absolutely does. And now he has to play information control on his own behavior and choices, which is often not fun simply because it's more stress to keep track of. Let alone if he's a player who plays to succeed at things, and now he's having to deliberately make choices that he knows are sub-optimal (or avoid making optimal choices...or metagame to launder the information he has into something his PC can act on), which is often frustrating.

What techniques would you use to control information, set up the properly eerie vibe, and handle the fact that players don't actually forget things just because their PCs are compelled to? How do you help those who do know, OOC, what's going on and how to deal with it to feel like they still can contribute without breaking character or metagaming?

The way I dealt with it when I ran a false hydra is that I didn't have the PCs forget. I never said to the players "your character doesn't remember this person/thing you as a player very clearly remember," nor did I erase NPCs and feign ignorance when the players asked about them. If there was something that the characters should forget, then I never told it to the players in the first place. I presented the reality of the game from the perspective of the PCs memories, so there were clear gaps, paradoxes, and strange events. Things like, the lady's man paladin waking up to find a woman's hair ribbon suddenly sitting with his possessions. The town apparently not having had a mayor since the last one was sent to an asylum over a decade previously. The party's carriage running over something but the party finding nothing when they got out to investigate. Lots of little circumstances that they shrugged off in the moment, but nonetheless built up to give them the sense that something deeply unsettling was going on in the town.

When it became impossible for the monk to ignore the weird stuff and he went off alone to investigate, I started the next act. After he noticed another oddity and walked into an alley, I told him there was the sense of overwhelming silence and I cut back to the inn. I said that the monk slammed through the front door, breathing heavily, with blood running down his arm, and I turned to the monk's player and said "you have no idea how you got here from the alley." A clarification that the character was just as confused as he was. The death domain cleric was suddenly missing a magic item, an armband that increased the DC of his Channel Divinity which he had found during the party's very first adventure. When they searched through their bags they found that they were missing a bunch of unused items from the bag of holding, several basic healing potions, and there was another backpack among their possessions. It was full of adventuring gear, tiny wooden carvings chronicling all of their adventures, and clues about closely-held secrets from the cleric's backstory.

The adventure lead to the party freeing the former mayor from the asylum and discovering that he'd started seeing a monster in town shortly after an accident cost him his hearing. They brought him back to the town and he told them about the monster he could see that they couldn't. The cleric put 2-and-2 together and cast Silence. It didn't take them long after seeing the truth to fashion earplugs and then go kill the false hydra. When they gutted it they found a recent body with some of the missing gear and a holy symbol to the cleric's secret god. They realized that they'd had a second cleric for the entirety of their adventures, but when he was eaten and erased from their memories they rationalized away the gaps it left. For example, they rationalized the second cleric's Turn Undead attempts as a magic armband that made the first cleric's turn attempts stronger.

All that being said, I don't recommend my approach to the "extra party member the whole time" for all groups. Heck, I wouldn't recommend it for most groups: players get super possessive of loot whether they're using it or not, so you need a huge amount of trust and regular check-ins for them to accept loot vanishing.

[Marcloure]

The way I dealt with it when I ran a false hydra is that I didn't have the PCs forget. I never said to the players "your character doesn't remember this person/thing you as a player very clearly remember," nor did I erase NPCs and feign ignorance when the players asked about them. If there was something that the characters should forget, then I never told it to the players in the first place. I presented the reality of the game from the perspective of the PCs memories, so there were clear gaps, paradoxes, and strange events. Things like, the lady's man paladin waking up to find a woman's hair ribbon suddenly sitting with his possessions. The town apparently not having had a mayor since the last one was sent to an asylum over a decade previously. The party's carriage running over something but the party finding nothing when they got out to investigate. Lots of little circumstances that they shrugged off in the moment, but nonetheless built up to give them the sense that something deeply unsettling was going on in the town.

Yup, that is the way to do it. One of the DLCs of Pillars of Eternity has a plot about a monster that affects memory, and the way the game does that is by mentioning past events and character that never actually existed in the game, but that now are true.

[Segev]

Random thought I just had while watching an AMV, of all things: what if dancing along to the music was as good as not hearing it for rendering the mind-wiping effect null? You can actually be aware of it as long as you dance to it.

Alternatively, those who're interacting with a falsified memory under its effects notably dance but don't notice themselves doing it.

Not sure where to go with that, but it hit me as a possible way to add some interesting "rules" to the scenario that could ramp up the creepy factor and/or provide more ways to deal with it IC.

[Witty Username]

I think I would run this as PCs immune in some way, like maybe they come in to a town with an established monster. So all the effects are on the townsfolk, maybe with a deaf npc that appears raving mad.

Kinda like a time loop plot, main characters tend to remember the loop, so the PCs would be in the know trying to figure what the break is.

For D&D, I think "bloody" horror works better than psychological horor. Intense physical threat and the horror coming from how to escape, with some NPCs or backup characters getting cheese grattered.

[Kane0]

I think Dungeon Dad did a video on this, should be a decent watch for info and inspiration

[Grim Portent]

But if the false hydra deletes people, why would the villagers call it a kidnapping? That implies they are still remembered, and missing. Did I miss something?

The original version doesn't delete people per se, just suppresses any memory of them and makes people try to explain away the oddities that result, but the oddities remain. People leave physical traces of their past, and the only ones the Hydra makes invisible is the blood and any body parts left behind by it's feeding. In the Red Herring version the Hydra doesn't make people forget about it's victims, it just makes them think something else happened to them. It's a lot less creepy of a concept imo.

A blacksmith gets a letter addressed to his wife, but he isn't married, he's never even been in a relationship. Wait? Why is this closet full of women's clothes? That's weird. Why is there a locket with a picture of me and a woman I've never seen in the drawer of the nightstand? Why has the spinster next door found a pair of worn men's boots in her cupboard? Who founded the town pub ten years ago, the property records say it was a guy called Barry but no one remembers a Barry?

People are meant to be subconsciously aware of what's going on and increasingly distressed in their lucid moments, their hands write messages that they cannot explain and so on, but the errant thoughts get smoothed over by the monster singing, which only pauses when it attacks someone or is eating.


I had a GM run a ghost story inspired by the False Hydra, in which NPCs were dissapearing from our memories as they vanished overnight from the town, but all the NPCs and PCs knew something was wrong. Diaries, clothes, missing spaces in memories, empty homes, census records. There was stuff saying that the vanished existed, but no one remembered ever even meeting them.

I was the only player who was familiar with the concept and I pegged it as a False Hydra after the first instance of us forgetting an NPC from the day before. I'd read the blog post it orignates from a few years prior, and even then it was quite unsettling for a good while. I think it being an actual False Hydra rather than a ghost story might have worked better for being creepy, as is the story was more tragic by the end.

[Ionathus]

I don't think I'll ever run a False Hydra or anything like it.

I've used minor "edits" on my players before (giving them an ancient tablet with incriminating info, they hand it to an NPC, when the NPC hands it back the info has been replaced), but I can't see myself basing a conflict or plot around those edits. I'm such a stickler for continuity that a False Hydra plot would be a nightmare for me. Even just the logistics of the song and the forgetting, and the PCs trying to probe the edges of what works and doesn't work, would be a headache and I would not feel good running it.

Not sure how my current players would feel about it either, though I expect if it was run well they'd enjoy it. I just can't guarantee I could ever run it to my own satisfaction, or theirs.

[Lord Torath]

So you need to hear the song to be affected by it, yes? Is its song magically audible anywhere in range? If you've got a bunch of smiths in a workshop all pounding out various metallic products, can they hear the song? What about the Innkeeper when he goes down to the cellar to check how many kegs of ale he has left? Or what if the local bard is putting on a performance in the inn with a roaring crowd? The alchemist who puts in hearing protection when making whatever he makes that involves small explosions in the process?

And doesn't the stupid false-hydra ever get hoarse, with all that continuous singing?

""I'm just asking questions, here"

[Veldrenor]

So you need to hear the song to be affected by it, yes? Is its song magically audible anywhere in range? If you've got a bunch of smiths in a workshop all pounding out various metallic products, can they hear the song? What about the Innkeeper when he goes down to the cellar to check how many kegs of ale he has left? Or what if the local bard is putting on a performance in the inn with a roaring crowd? The alchemist who puts in hearing protection when making whatever he makes that involves small explosions in the process?

And doesn't the stupid false-hydra ever get hoarse, with all that continuous singing?

""I'm just asking questions, here"

All of that depends. The concept is pretty flexible, and how you answer those questions can lend their own flavor to your false hydra. When I ran it the song wasn't magically audible, which is how the party ended up solving it. But I went with the erasure version of the song rather than the suppression version: once a memory was gone it was gone, and walking somewhere that you could no longer hear the song wouldn't suddenly restore the missing memories. So the smiths, the innkeeper in his cellar, the bard performance, none of that matters. They don't remember what they've lost and if they see the creature then they're bound to stop the noise-making activity to flee, at which point they can hear the song again and forget. As for getting hoarse, maybe it does and that's why the version I ran had multiple necks & heads like a hydra. Or maybe it never gets hoarse because it's a supernatural horror monster whose defense and weapon is its song.

[Bohandas]

What is a False Hydra, in this context?

Apparently The Silence (and/or the Twilight Zone episode with the disappearing airmen)

[Batcathat]

So you need to hear the song to be affected by it, yes? Is its song magically audible anywhere in range? If you've got a bunch of smiths in a workshop all pounding out various metallic products, can they hear the song? What about the Innkeeper when he goes down to the cellar to check how many kegs of ale he has left? Or what if the local bard is putting on a performance in the inn with a roaring crowd? The alchemist who puts in hearing protection when making whatever he makes that involves small explosions in the process?

I think if I ran something like a False Hydra, I would try to include quite a lot of "flaws" like this, it feels like it would both make it easier for the characters to solve the situation and less likely for the players to get upset about the concept.

I must say some of the stories in this thread are kinda tempting me to try it. It's obviously a potentially problematic concept, but with the right setup, the right players and a bit of luck, it seems like it could be pretty fun.

[Grim Portent]

I think if I ran something like a False Hydra, I would try to include quite a lot of "flaws" like this, it feels like it would both make it easier for the characters to solve the situation and less likely for the players to get upset about the concept.

I must say some of the stories in this thread are kinda tempting me to try it. It's obviously a potentially problematic concept, but with the right setup, the right players and a bit of luck, it seems like it could be pretty fun.

It can be very fun, but it's a horror monster, a proper horror monster. It's a big weird creepy puzzle more than a boss or anything, once you figure out what it is it's not supposed to be all that threatening unless it's already grown to a huge size. Even then without it's song it's relatively weak for a creature that size, especially in D&D terms, so a fight has the potential to feel anticlimactic.

I'd need to check the blog post, goblinpunch (which is currently throwing me a trojan alert for some reason,) to be sure I've not forgotten something but the idea is that it only attacks people who are alone and vulnerable, because during combat and feeding is the only time it's able to be directly percieved as it needs to stop singing in order to bite and swallow. If it attacks someone who can fight back and it gets hurt it retracts it's head or heads back to it's lair and resumes singing so it can recover and try again later.

When it gets big enough the song makes people walk towards it so it can eat them, then it moves on towards the next population center after eating everyone nearby. I think there was something about some people becoming enthralled as minions of some sort rather than being eaten, but I can't remember what they did for the hydra.

It's really not a D&D monster, the concept was systemless and the originator has his own homebrew horror system. It would work great in proper horror games, or games where losing is a more accepted narrative possibility. Dark Heresy, Call of Cthulhu or World of Darkness for example. D&D struggles with it more because it conceptually goes against a lot of the accepted norms of the genre.

[Kvess]

I ran a false hydra following Sly Flourish's suggestion for The Styes, from Ghosts of Saltmarsh. It's a very subtle variation, where players discover that they had 'forgotten' about a druid who was travelling with the party the whole time!

One of my players was a Doctor Who fan and was very excited when he realized what was happening.