Will the Demonomicon of Iggwilv Break My Campaign?

[GuestEleven]

I am running OOTA currently and the party is level 7 at the moment. The most active player is a worshipper of Torm and from a line of demon slayers. I would really really like his character to get the new Demonomicon from TCOE, but I was wondering if it would be too early.

Edit: Listed Tyr instead of Torm for the player's deity.

[Unoriginal]

Well that will definitively change your campaign majorly.

Question: why do you want this worshiper of Tyr to get a powerful demonic artifact?

[GuestEleven]

It would be equally useful for a demon hunter as it would any fiend. Extra damage to fiends, double proficiency when discerning information about demons, and empowered fiend trapping. Also I misspoke, Torm is their god.

[ProsecutorGodot]

Well that will definitively change your campaign majorly.

Question: why do you want this worshiper of Tyr to get a powerful demonic artifact?

I can only assume to place bait for him to destroy it... Which is, um, quite outside of his abilities at level 7.

Unless the player has expressed interest in this, I'd avoid it.


It would be equally useful for a demon hunter as it would any fiend. Extra damage to fiends, double proficiency when discerning information about demons, and empowered fiend trapping. Also I misspoke, Torm is their god.
It gets more dangerous the more it's used, assuming the detrimental properties aren't so severe that the character automatically dies before they've had the chance... which can happen.

[MaxWilson]

Ability to cast 9th level Planar Binding multiple times per day as an action instead of an hour-long complicated ritual? Yeah, that's going to break your campaign, especially if there's a Diviner or Chronurgist in the party.


It gets more dangerous the more it's used, assuming the detrimental properties aren't so severe that the character automatically dies before they've had the chance... which can happen.

I assume you're talking about the Containment thing ("possessed when you finish a long rest")? Aside from simply not trapping any fiends in its pages, once you know about the detrimental property it's also easy to circumvent. Just have someone else take their rest shortly before you start your own, and then ten minutes before you finish your rest have them toss the Demonomicon in a Rope Trick until you're done resting.

[GuestEleven]

Ability to cast 9th level Planar Binding multiple times per day as an action instead of an hour-long complicated ritual? Yeah, that's going to break your campaign, especially if there's a Diviner or Chronurgist in the party.

Didn't consider the binding. Good call.

[Unoriginal]

It would be equally useful for a demon hunter as it would any fiend.

Given its negative effects, only a demonist would find it worthwhile.



Ability to cast 9th level Planar Binding multiple times per day as an action instead of an hour-long complicated ritual? Yeah, that's going to break your campaign, especially if there's a Diviner or Chronurgist in the party.

There's also that part.

[ProsecutorGodot]

I assume you're talking about the Containment thing ("possessed when you finish a long rest")? Aside from simply not trapping any fiends in its pages, once you know about the detrimental property it's also easy to circumvent. Just have someone else take their rest shortly before you start your own, and then ten minutes before you finish your rest have them toss the Demonomicon in a Rope Trick until you're done resting.

I'm also talking about the major and minor artifact property.

Also I'm not entirely sure that an extradimensional space fully qualifies as a different plane of existence. If anything, Antimagic Field implies that a portal to a different plane of existence is wholly separate from an opening to an extradimensional space.

Detrimental artifact properties are scary... it's considered a minor effect to have any type of rest prevented for other creatures while within 300ft of you (not the artifact).

The major detrimental effects are almost all debilitating.

[GuestEleven]

Given its negative effects, only a demonist would find it worthwhile.


I have to disagree. If I for instance were someone that hunted demons I would heavily consider using this book as a means to my ends. It would just really depend on your qualms in regards to how you dealt with the demons. I also like the archetypal story of someone using an artifact initially for good and slowly being corrupted by its use. I already mentioned it, but the fiend trapping and fiend scourging are just too useful to not be considered. Not to mention he is playing the daughter of one of my old characters, a demon hunter who had a demon hunting brother played by this same player. Our primary goal was collecting the Black Scrolls of Ahm which have a very similar vibe to the Denominomicon.

[JackPhoenix]

Don't know about your campaign, but posting copyrighted content definitely breaks the forum rules.

[Sigreid]

The minor and major detrimental properties could be a big deal. I've actually never considered the drawbacks from an artifact to be worth the benefits for my characters. I mean they usually get around to "You're dead and unressurectable now.

As far as the possession thing goes, I think just in a bag of holding is technically other dimensional space.

In a secure chest definitely is.

[GuestEleven]

Don't know about your campaign, but posting copyrighted content definitely breaks the forum rules.

I'll have to fix that then.

[MaxWilson]

I'm also talking about the major and minor artifact property.

(A) Also I'm not entirely sure that an extradimensional space fully qualifies as a different plane of existence. If anything, Antimagic Field implies that a portal to a different plane of existence is wholly separate from an opening to an extradimensional space.

(B) Detrimental artifact properties are scary... it's considered a minor effect to have any type of rest prevented for other creatures while within 300ft of you (not the artifact).

The major detrimental effects are almost all debilitating.

(A) Personally, I consider extradimensional spaces to be even further away than other planes, and FWIW the Sage Advice Compendium (https://media.wizards.com/2020/dnd/downloads/SA-Compendium.pdf) has this to say on the subject:


Are extradimensional spaces, such as a demiplane or the space created by rope trick, considered to be on a different plane of existence? An extradimensional space (aka an extraplanar space) is outside other planes. Therefore, if you’re on the Material Plane and your foe is in an extradimensional space, the two of you aren’t on the same plane of existence.

I'm happy to ignore Sage Advice when it contradicts RAW, but in this case I don't believe RAW says anything either way. "Ask your DM." Anyway my real point is that making it happen at a specific instant in time (when you finish a long rest) is a dumb design because it makes it easier to circumvent. The fact that their own Sage Advice ruling indicates that a 2nd level spell should circumvent the problem is just more evidence.

(B) I was asking about the "more dangerous the more it's used" part.

There are indeed some horrific "minor" detrimental properties (disadvantage on saves vs. spells) as well as some truly minor ones (no sense of smell, weight drops by 1d4 x 5 lb., destroy holy water within 10' of you) and even minor "major" ones (Geased by artifact for 5d10 psychic damage per day, need to wound yourself for 1d4 HP as a bonus action before using an artifact action), and major major ones (vulnerability to all damage, inability to speak). But I don't think any of them get more dangerous the more an artifact is used.

[ProsecutorGodot]

(B) I was asking about the "more dangerous the more it's used" part.

There are indeed some horrific "minor" detrimental properties (disadvantage on saves vs. spells) as well as some truly minor ones (no sense of smell, weight drops by 1d4 x 5 lb., destroy holy water within 10' of you) and even minor "major" ones (Geased by artifact for 5d10 psychic damage per day, need to wound yourself for 1d4 HP as a bonus action before using an artifact action), and major major ones (vulnerability to all damage, inability to speak). But I don't think any of them get more dangerous the more an artifact is used.

Yea, that was more in respect to the fiend trapping part, which isn't safe from the start because 1d4 fiends are trapped from the very beginning.

Here's my biggest gripe about it... None of this information is exactly hidden from the player when they attune to it right? Assuming they're lucky and have artifact properties that don't kill or maim them, don't they immediately know that spending a long rest attuned to it is a high chance of possession?

This isn't exactly supposed to be a good or orderly item, it's the spawn of things even chaos demons don't want to know about. I'm honestly surprised it's not really "cursed" aside from having those artifact properties.

I feel like it should be a dangerous item to have but all you've really shown me is with a bit of luck and a small amount of ingenuity you reap all the benefits with next to no downside.

[MaxWilson]

(A) Yea, that was more in respect to the fiend trapping part, which isn't safe from the start because 1d4 fiends are trapped from the very beginning.

Here's my biggest gripe about it... (B) None of this information is exactly hidden from the player when they attune to it right? Assuming they're lucky and have artifact properties that don't kill or maim them, don't they immediately know that spending a long rest attuned to it is a high chance of possession?

This isn't exactly supposed to be a good or orderly item, it's the spawn of things even chaos demons don't want to know about. I'm honestly surprised it's not really "cursed" aside from having those artifact properties.

I feel like it should be a dangerous item to have but all you've really shown me is with a bit of luck and a small amount of ingenuity you reap all the benefits with next to no downside.

(A) Cool, thanks for explaining. Just curious. I was trying to make sure I hadn't overlooked other dangers.

(B) One of my bigger gripes with 5E is that it isn't designed with any real thought for information management: what the experience of receiving or not receiving certain information will look like from the players' perspective. It shows up in monster stat design (dearth of textual descriptions for monster appearance, or non-game-jargon textual descriptions of how monster abilities work), in magic item design, in class design, in adventure design...

In this case I absolutely agree that spilling the beans up front leads to a relatively poor player experience.

[Pex]

A 15th+ level Devotion Paladin at least doesn't have to worry about the possession.

[MaxWilson]

Didn't consider the binding. Good call.

You could give it out and just remove the Planar Binding action. I think that would be fine.