D&D (2024) Knowledge Skills - houserule idea

[Yaarel]

CR shouldn't even be involved in the equation. People are more likely to know the nature and traits of a high CR red dragon than an obscure CR 1/2 monstrosity.

Base the DC on how common the creature is in stories, with a lesser contribution from how commonly it is actually encountered, and zero contribution from its CR.

I was wondering if the higher the CR the more people know about it and the easier it is to get specific information.

 

[Sword of Spirit]

I was wondering if the higher the CR the more people know about it and the easier it is to get specific information.

Depends on the creature. More people probably know about red dragons than boggles, but more people also probably know about badgers than atropals.

 

[Stormonu]

Using CRs has an issue; the Elephant (CR 4) is probably one of the best examples where a CR approach doesn't make a whole lot of sense whereas a "rarity" would be more appropriate (i.e., those who live where they exist would have an easier time identifying and knowing about them than someone half-way round the world where they've never been seen - and then you get into things from other planes of existence...).

CR might be useful for a starting point, but there has to be factors of rarity involved as well, and that gets ... complicated.

 

[Yaarel]

Depends on the creature. More people probably know about red dragons than boggles, but more people also probably know about badgers than atropals.

Using CRs has an issue; the Elephant (CR 4) is probably one of the best examples where a CR approach doesn't make a whole lot of sense whereas a "rarity" would be more appropriate (i.e., those who live where they exist would have an easier time identifying and knowing about them than someone half-way round the world where they've never been seen - and then you get into things from other planes of existence...).

CR might be useful for a starting point, but there has to be factors of rarity involved as well, and that gets ... complicated.

I wonder if the DC formula can be something like:

Knowledge DC = Rarity − Source − CR

RARITY
Common = DC 10
Uncommon = DC 20
Rare = DC 30
Very Rare = DC 40

SOURCE
Rumor = -0
Personal = -5
Expert = -10

CR
The more dangerous a creature is, the more interest, attention, fascination, and knowledgeability about it. Only the Rarity might offset this tendency.

 

[evilbob]

Unfortunately "rarity" isn't a thing when it comes to monsters. And even if it were, it wouldn't necessarily carry across different campaigns (i.e. dragons are common in this world and super rare in that one). Ultimately it's subjective, which isn't useful for designing a rule. CR seems to be the best we have.

 

[Horwath]

I wonder if the DC formula can be something like:

Knowledge DC = Rarity − Source − CR

RARITY
Common = DC 10
Uncommon = DC 20
Rare = DC 30
Very Rare = DC 40

SOURCE
Rumor = -0
Personal = -5
Expert = -10

CR
The more dangerous a creature is, the more interest, attention, fascination, and knowledgeability about it. Only the Rarity might offset this tendency.

this isn't 3E, that you can have this big of a gap in skill DCs, everywhere you have a jump of 10, you should reduce it to 3 or 4.
skills in 5e, from 1st to 20th level, mostly go from +7 to +17, counting in expertise and ability jump from +3 to +5
in 3E it's +7 to +30 or more, and +10 or +20 items for a skill ware not that expensive.