I am not even sure I understand your question, in that I don't understand the role any D&D/D&D-derived rule set would play in establishing the mood and story-telling portion of a game session.  To me, that is all about players reacting in caharcter to the DM narrative, the DM responding,and following give and take between players and DM.  Frankly, I don't even see the need for rules for that.

I did put together a somewhat slow burning weird horror adventure for AS&SH that I ran several times at conventions - a sort of Flesh + Blood meets High Plains Drifter.   I thought the setting, rules and the classes really worked well with the adventure.  I wouldn't have written the same thing for AD&D or BX.  From  what I could tell I think it also worked with the players expectations for the game system.

I don't think AS&SH is necessarily all that much more granular than B/X or BECMI.   To me it plays like a combination of those two with some AD&D seasoning.   I do think fighter types tend to be a bit more powerful at lower levels so that is something to think about.  The pulp fantasy classes and other trapping should also help with the weird fantasy vibe as they don't have the Tolkien high fantasy overlay (with elves, dwarves, halflings etc.) that you have in B/X.   
 

Hi again, BenA718.

I ran Ynn in my AS&SH game not long after it came out (the PCs had tried to assassinate their patron in Brigands Bay and cocked it up SPECTACULARLY and had to get lost in a HURRY; so: Ynn).

I found that very little was needed from me to creep them out -- they were lost and confused and oddly obsessed with the materials of the various strange portals trying to figure out patterns -- and it was the lack of a pattern that really started creeping them out. All I had to do was present them with what's in front of them.

Importantly, in Ynn, there are a lot of INTELLIGENT creatures who have been dealing with that environment for a very long time. So there's lots of room for faction play and RPing, which is good because the few times they tried going toe-to-toe with something they got their asses handed to them. Plus, terrible bad luck with surprise dice and a giant preying mantis. But reaction rolls and charisma adjustments become IMPORTANT.

In my half-assed Hyperborean lore, the clan of Hyperboreans that developed Ynn when theirs was a multiverse-spanning empire of eldritch power degenerated along with the rest of the culture but rather than falling into Xathoqqua worship and terrestrial squabbles went strange and fey and and feral in their garden realm -- and that's the Sidhe and the Idea of Thorns.

Rules-wise, I think the most friction between setting and system in Ynn comes in resting. They might end up harried and desperate until they figure out to retreat "upward" before resting.

BenA718 wrote:

Handy Haversack, that's pretty much exactly what I needed to know, thanks!

I have run Ynn many times, I usually have it sitting just off camera waiting for a PC to stumble upon a journal describing it and how to enter it in a journal picked up among loot. Anyone/anything describing Ynn always uses the most exultant and flowery praise, more than enough to get PCs to enter, quickly get lost, and run for their lives. Even in a convention setting, it never fails to freak players out.

I wish Emmy Allen would do a POD version of her ice age RPG! I feel like it could have definite AS&SH applications -- made me think especially of when BA23's players ended up rather far back in the past. But, yes, Ynn is an excellent product from a sharp-as-a-magic-spear-that-cuts-through-anything gaming mind.

Like I said in your other thread, BA718, I throw adventures from all over the damn place at AS&SH and never find that it's the systems that create friction but the level of skill with information presentation and understanding that the adventure writer brings to the table, vis-a-vis my prep time and smoothness in running it.

Never heard of Wolf-Packs; looks great!