I stumbled upon a reddit thread about preferred campaign settings a while back, and it got me thinking about published settings that I have played or thought about running. Upon some reflection, I think the only published setting I've run was Midnight, while I also played in Eberron and have dreamed of the Wilderlands of High Fantasy. Ultimately, Eberron is not to my taste stylistically, and I think the problem with the Wilderlands is that they're just too big. I guess as a DM, I'm just not comfortable running a setting that I can't fit inside my head. So I'm not sure I'll ever be able to do more than steal names and hex descriptions from it and do it homage.
Midnight, though. Mmmm. A grim and doomed world, defiant of tropes, where the Good Guys will almost certainly lose. It's the sort of world where powerful magic is uncommon, and resource management (even of mundane resources like rations) is critical to survival. Even town is dangerous, since villagers might turn you in for a reward, or regard you with fear, and public opinion is another resource to be carefully considered. Thus Midnight seems, in some sense, the Old School-iest of published 3.x settings, at least in lethality and resource management. I never really felt like 3.x or other modern d20 systems did Midnight justice. This may have been because we included too many splatbooks; I may or may not have been guilty the first time, where I was playing and built Thagg the Giant-Blooded Feral Orc-Dwarf Berserker who, uh... was perhaps ever so slightly overpowered. Suffice to say that Thagg never really feared for his life, nor understood the concept of fear (especially when embiggened to Huge size via enlarge person). That particular campaign kind of played out like a standard 3.5 campaign, except all of the encounters were wilderness encounters because we stayed away from town, and there was no treasure.
The second encounter I had with Midnight was using True20, which I briefly mentioned here. Again, supplements really mucked with things, and I had a hard time generating the kind of fear and resource management that Midnight runs on. Too many Conviction points and well-chosen synergistic abilities.
It's a pity I don't know of any systems where PCs actually fear for their lives and can be bothered to track mundane resources like torches and rations...
Oh wait, yes I do. I kind of worry, though, that running ACKS Midnight would be, well... too lethal. There would be a few other systemic issues too, I think. If town is dangerous, it suddenly becomes much harder to recruit henchmen, which means replacing casualties is more difficult. Additionally, since there really isn't treasure per se in Midnight, levelling slows to a crawl because no XP from treasure. I guess you could award XP/GP for captured enemy armament - "OK, you killed a 12-orc patrol and they were each wearing 50 GP of armor and carrying an 8-GP sword, so that comes out to 696 XP. Also they had mules carrying food!" The high-level domain game would also be kind of screwed-over by running the game in Midnight; no matter what you build, or where you build it, the orcs are coming to topple your towers and kill your peasants. It would be a very defensive domain game.
Probably the best way of running ACKS in Midnight would be a 'Robin Hood'-style game. The PCs are a band of rebels and merry woodsmen, free-riders, or pirates. The wilderness of ACKS is somewhat more dangerous than that of Midnight, where you mostly need to worry about patrols and undead rather than great flocks of gryphons, which means that low-level wilderness play is much more viable here than it normally is in ACKS. The wilderness evasion rules would get used pretty often here, I think, and man ACKS' naval rules would work great for a Corborn pirate instantiation of this... In any case, the game would center around raiding enemy encampments, evading reprisals, and attempting to win the favor of the local populace to gain safe havens and recruiting sources in towns. A very different game... I think Thieves might actually be useful. Hero Paths would be tricky; maybe just build extra sets of proficiencies, associate them with paths, and give them out at a uniform rate. Magic changes could be handled fairly easily by merging the cleric list into the mage list, dropping healing, rejiggering the tables a bit, and maybe using Alex's proposed spell point rules. The power nexus rules could be easily converted so that they provide a source of something much like Divine Power for item creation and research. Charms are straightforward, and really much like the antivenom rules we've been using already, and covenant items would be pretty easy too. Building new race/class combos would be annoying, but that's not insurmountable.
So I guess I'm adding Midnight to the queue of ACKS settings to run...