Do You Care About Cosmology?

I don't think it is particularly interesting or important, unless it creates actually gameable opportunities.

Edit: assuming a D&D type game...

As a player:
Having some very basic information, if relevant to the character's origin (ie does this drow know about Lloth)
I'd prefer more than basic information if I was playing a character using 'divine' magic (ie a cleric/priest, paladin...), even if the information from the DM is 'make something up and let me know'.

As a worldbuilder:
I incline to a top down approach, and charting out some basic structure. Its' easier to hop into a sandbox if I know where the box is, how granular the sand is, and what type of objects are in the box with the sand (possibly buried).

[Does Teleport function because it folds a 4th physical dimention, or does Teleport instead Jaunt the characters across a planar boundry and through the Astral plane?
Is version one why characters can Teleport within Sigil, but cannot exit with this type of magic?
Do both versions of Teleport exist in the campaign world, but version one is the most valuable secret of an elite organization who specializes in infiltration?...]

Also: material to flavor those Knowledge (religion)/Religion, Knowledge (arcana)/Arcana checks with.

I clicked the middle option but really I feel like you can separate games into two groups:

1) Those heavily informed by their cosmology, where understanding it is key to understanding the setting, and liking the setting and liking the cosmology are one and the same.

2) Those for whom the cosmology is mostly irrelevant for most of actual at-table time.

And most games are the latter, today.

Also, there seems to be an assumption in the options you provide that cosmology is an inherent value-add.

I do not think that this is true.

I think in quite a lot of cases, a game's setting is damaged or even ruined/rendered totally unattractive by cosmology-based choices. I don't want to get into a squabble about which exact settings I might be thinking of here, but there are definitely games I wouldn't want to play because there's something gross or weird (usually unintentionally/thoughtlessly so, if it's intentional it can be cool) about the cosmology. Like, maybe whoever wrote the cosmology is assuming faith in the gods is inherently virtuous and lack of faith is inherently malign or sinful, but has not consciously written the setting that way - so it's an assumption of the cosmology, but it's not intentionally designed to talk/think about that, it's just taken for granted.

I will say I find Draw Steel!'s cosmology to be an example of a value minus proposition, I think Matt Colville is pretty cool and has cool ideas but I think he really wildly overestimates how popular Moorcock-ian Order vs. Chaos stuff is to literally anyone except him (including his players from the way he describes games he'd DM'd!!!), and him baking that into the setting, as well as setting some pretty awful or even monstrous-sounding gods as supposed "good guys" is perhaps... not going to be helpful to Draw Steel! in the longer term.

I think that's a Type 2 game though - it doesn't really matter at the table where these powers are coming from and so on. You could certainly use a different cosmology in a way you couldn't really with say, Werewolf: The Apocalypse.

As reading material, it can be interesting, as gaming framework, I don't know that I can remember a solid concept let alone one which would get buy in from the modern playerbase.

As a player, I care about the cosmology only as much as it makes the world feel more lived in and if I'm going to go on adventures in those places.

As a GM, I love reading about extraplanar stuff.

Only if it matters.

The best way to make it matter is mechanics. Have the cosmology actually mean something to the dice and tactics. Especially for clerics, paladins, or others that would draw magic directly from the cosmology. That sort of building is awesome.

The other way to make it matter is for the backstory to actually come up in the game. Ideally it's part of a plot. At minimum it's referenced by NPCs.

But if it's just random backstory? That's fun and all, but time at the game table is a bit of a precious commodity. Let's spend it playing the game, not telling campfire stories.

I’m another who likes it when it matters in play, but otherwise generally doesn’t care. This is in part a getting-older thing: I’ve now read many cosmologies and contributed to making some, and I have been there and done that. It’s possible to surprise and delight me still, either with a fresh implementation of older ideas or something I hadn’t thought about before. But doesn’t happen much anymore.

doctorbadwolf said:

So let’s say my game has a unique creation story that informs all of my world building, the nature of all beings, especially the adversarial beings that threaten everything, and underpins how magic works and what it even is in the world.

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Cool. So far, at least. Does it affect the design? If not, it's wasted, IMO.

doctorbadwolf said:

Do you want to know about it, as a player? Do you read all you can, or ignore it and only bother learning the “right now” stuff that directly affects your character?

Click to expand...

If I'm playing a cleric, or if the cosmology includes accessible planes, yeah, I want a nice precis, and, ideally, more to read later

doctorbadwolf said:

Do you want cosmology to matter, with mechanical weight put behind it?

Click to expand...

If it is included past a couple paragraphs, yes.

Never had the beverage... but would be happy to try one.

I have been blissfully running a Ptolus campaign since 2006. Its world, Praemal, has no access out to the other planes, and any planar beings tricked into going there are trapped. And it's been more than fine. (One of the PCs has met a drunken archangel who's miserable about being trapped, but too responsible to explain the grand design to the mortal. The player was profoundly disinterested.)

For Shadowdark, I idly think about what a fresh cosmology would look like, going from first principles of creating only what's needed to explain what shows up in the game world. But so far, other than the existence of (probably) a good afterlife and a bad afterlife, and wherever elementals, fey and undead come from, it hasn't really been an issue. I suspect I can probably just make up a few names and vague hints and be good more or less indefinitely.

As a player, I'd be interested in the light version, primarily how it might affect my character or the expedition that we're on.

As a DM, I'm fascinated by this sort of thing and have been designing entire worlds with different assumptions on how things came to be and what machinations are going on in the background, mortal or otherwise.