Should a TTRPG have a singular Core Rulebook or more?

[Reynard]

Sure the question is what "the tools" constitute. I suspect we'd not agree on that.

Mostly the "tools" are the math underpinning the system, a clear explanation of intent behind both the system.broadly and its play elements, and some well crafted examples of varying complexity to get you started. A good toolkit has all of these, though it is common for specific game systems to emphasize one over the others.

 

[Eyes of Nine]

Has anyone taken a stab yet at defining "Core Rulebook"?

tl;dr, I propose one possible definition of "Core Rules" - It's the core conflict resolution mechanism, everything else is GM prep (even when that prep is provided by a publisher)

One way to see this is "Core" means just the rules, whether explicit (how to resolve a skill check); or implicit (how to create/prep a class; followed by how to create a character with the class the GM or a publisher (including WotC) prepped).

Or, we could define this as "all the stuff currently in the 5e MM, PHB, and DMG" - that's core books because that's what WotC calls them.

I mean, is the MM considered core? Or is it just prep created by a publisher? A good chunk of the DMG is optional rules and magic item tables - are they really core? Or just prepped content?

Truly, if we boiled D&D 5e down to just the "rules", I'm pretty sure I could fit that into a single 64-page zine. Actually, maybe even a 1 page pamphlet.

Actually here's an attempt right here

When there's uncertainty in the outcome of any situation in the game, roll a d20. If the roll plus modifiers is higher than the Difficulty Class the GM sets, the outcome goes as the player wanted. If not, the GM gets to apply some sort of penalty (damage, condition, or something else) based on the fiction of the moment or their prep (monster effects, magic effects, et al are part of GM prep). Difficulty Class may also be called Armor Class; or even something else.

Exception: In some cases, based on GM prep, an effect may be something a character (either PC or NPC) wants to resist. In this case, a "Saving Throw" is made, wherein the character rolls a d20, applies modifiers, and if the roll is equal to or higher than the Difficulty Class of the effect (based on GM prep), then the effect is avoided. If it is lower than the Save DC, then the effect is applied

And of course maybe another 10-15 pages devoted to "How to Prep" - like how to create character classes, heritages/races, feats, monsters, backgrounds, magic items, equipment, spells.

Sections on "how to balance"; "how to create encounters"; "how to handle non-combat 'stuff'"; "how to make the game fun"; "how to adjudicate" etc doesn't seem core to me.

Even some of the stuff in the "Combat" section doesn't seem core - it seems like WotC prepped content based on default setting assumptions about the pseudo-European medieval fantasy setting of Faerun. Take the Jump rules for example. They apply well in the default D&D setting. BUT if you were to prep/create a setting on a low-gravity planet, then the Jump rules would be different.

 

[delericho]

For any game other than D&D (and near-D&D games like Pathfinder and A5E), I'd argue that if you can't fit it in to a single 250ish-page book, you're probably doing something wrong. Actually, the same is true of D&D, but I give that a pass for tradition.

That said, almost every additional book published for almost every edition of almost every single game after the core rulebooks has generally made the game worse, so maybe there's an argument for a bigger core...

 

[Celebrim]

Has anyone taken a stab yet at defining "Core Rulebook"?

No, and I do think it's pretty critical to understanding the answers to the question.

tl;dr, I propose one possible definition of "Core Rules" - It's the core conflict resolution mechanism, everything else is GM prep (even when that prep is provided by a publisher)

I think that's entirely reasonable. And I think it explains one category of answers - along the lines of "But I only need a 64 page book to play a game endless for years!".

I don't dispute that in the slightest.

I mean, is the MM considered core? Or is it just prep created by a publisher? A good chunk of the DMG is optional rules and magic item tables - are they really core? Or just prepped content?

They are all just prepped content. By your definition, virtually everything, is just prepped content. But this gets back to my answer. Sure, I can play a game with just a conflict resolution mechanism and prep all my own content, but really why would I want to do that? It's a ton of work just prepping my scenarios for play much less creating all the other stuff needed to run a scenario. Of course you don't need a monster book. Of course 10 pages of rules for making a monster is enough for infinite amounts of play. But really, there is enormous value in being able to off load so much of that to a professional.

I mean seriously, we don't even technically need a rule book. We don't need to buy anything. I have written my own systems. But please I'd rather give someone the money to do that work most of the time.

 

[Reynard]

Has anyone taken a stab yet at defining "Core Rulebook"?

I thought it was kind if self evident, but I'll take a stab anyway:

All the rules necessary to engage with the game's stated play loop and fiction/fantasy.

 

[Thomas Shey]

I thought it was kind if self evident, but I'll take a stab anyway:

All the rules necessary to engage with the game's stated play loop and fiction/fantasy.

You may have answered this earlier but I don't want to conflate you with someone else: does a method of describing how to build opposition make enemy books not-core? I'd suggest that with game systems that are at all detailed, that suggests a mandatory level of GM workload that most people would probably balk at in many genres.

 

[Reynard]

You may have answered this earlier but I don't want to conflate you with someone else: does a method of describing how to build opposition make enemy books not-core? I'd suggest that with game systems that are at all detailed, that suggests a mandatory level of GM workload that most people would probably balk at in many genres.

My personal opinion is that your core rules show you how to make enemies, and give you enough examples to be useful but not so many that they bloat the rules.

 

[Jolly Ruby]

For D&D-like TTRPGs I like the idea of a rules book and a bestiary. However I think a game master focused book is unnecessary, at least as a "core book". If the players need to read the rules it's better when they know all the rules.

 

[Thomas Shey]

For D&D-like TTRPGs I like the idea of a rules book and a bestiary. However I think a game master focused book is unnecessary, at least as a "core book". If the players need to read the rules it's better when they know all the rules.

The PF2e Gamesmaster book is useful, but not necessary; on the other hand, the Player's book is quite large.