I think the Darkhallow has been overlooked in the series for the significance of it's event, it's design, it's intended purpose and potential.
Upon re-reading
Dead Beat for the hundreth time, it really struck me the power of the Darkhallow.
From the exchange with Queen Mab:
Know this, mortal: Should Kemmler's heirs acquire the knowledge bound within the Word, they will be in a position to gather up such power as the world has not seen in many thousands of years."
"What? How?"
"Kemmler was"—Mab's eyes grew distant, as if in memory— "a madman. A monster. But brilliant. He learned how to bind to his will not only dead flesh, but shades—to rend them asunder and devour them to feed his own power. It was the secret of the strength that allowed him to defy all the White Council together."
I added two and two and got four. "The heirs want to call up the ancient spirits," I breathed. "And then devour them for power."
Mab's deep-green eyes almost seemed to glow with intensity. "Kemmler himself attempted it, but the Council struck him down before he could finish."
I swallowed. "What happens if one of his heirs is able to do it?"
"The heir would gain power such as has not been wielded by mortal hands in the memory of your race," Mab said.
"The Darkhallow," I said. I rubbed at my eyes. "That's what it is. A ritual, tomorrow night. Halloween. They all want to be the one to make themselves into a junior-league god."
So we learn what the Darkhallow is - a ritual of ascension. And yet, also not. Harry says it's more a spell than a rite - the difference I seem to remember is where the power comes from. The destruction and consuming of spirits by the performer imbues them with the power of a "junior-league" god, as Dresden says. Mab says that kind of power hasn't been wielded by mortal hands in the memory of the human race. At face value, that could be 10-100 thousand years. But I think Dresden only later realises that he might have underestimated how much power was in play.
Cowl kept on chanting, and I saw his body arch with tension. Over the next minute or so, he actually, physically rose above the ground, until his boots were three or four inches in the air. His voice had become part of the wild storm, part of the dark energy, and it rolled and boomed and echoed all around us. I began to understand the kind of power we were dealing with. It was power as deep as an ocean, and as broad as the sky. It was dark and lethal and horrible and beautiful, and Cowl was about to take it all in. The strength it would give him would not make him a match for the entire White Council. It would put him in a league so far beyond them that their strength would mean virtually nothing.
It was power enough to change the world. To reshape it after one's own liking.
So I think we can see it dawns on Harry that should Cowl succeed here, the world will change. There will be a new order to things, and Cowl, or rather the thing that Cowl would have become, would be in charge.
Even Corpsetaker said something about granting Harry autonomy and a principality of his choice, effectively making Harry a lord or king under him. Probably of a good portion of the USA, maybe all of it.
That's the kind of world-shaping power in play.
What's curious is what the other supernatural nations would have done. We know that Cowl (or whoever had succeeded, but probably Cowl) would have wiped out the Senior Council and effectively destroyed the White Council while the Red Court would have cleaned up the dregs. Without the White Council, humanity would have been less protected and more open and brazen attacks would have occurred. The smaller Accords nations certainly would have gone to ground, or served or been wiped out. Vadderung and Ferrovax likely would have retreated unless forced to fight, and I suspect they might have waited for a more certain victory. The Vamps and others likely would have served (or at least allied) with this new entity, which we must assume is much stronger than the Lords of the Outer Night (Red King inclusive), and Drakul etc. The Jade Court would just have waited things out I imagine, given that's all they apparently do...I also can't see the Faeries just lying down. But they might have stayed back. This being would have been beyond Mab and Titania, per WOJ. Probably not beyond the Mothers but it's hard to say how close. But the Mother's don't do direct fights like that - although curiously given the conversation with Kumori (and the theory that one of Mother Winter's aspects is that of Death), one might assume Cowl (as a god) would have attempted to kill Mother Winter in order to "end death" as Kumori puts it. Can't imagine Mab would have take that lying down. Then again, Cowl seems to work with Outsiders so they might have given him the opening he would have needed.
We also know that Ethniu was ready to go with an army and her superweapon and nigh-invulnerability. We know that The Outsiders had a serious assault or two ready to go, led by He Who Walks Before. He Who Walks Beside also clearly has many interweaving goals, which the Darkhallow might be linked to. We know that Nicodemus had several plans on the go, some of which involved stealing high-value supernatural relics, and corrupting powerful people including the Archive. Not to mention Drakul clearly also has some similar operations to Nicodemus going on. My guess is Nicodemus, Drakul etc. would have gone to ground. Maybe paid their respects eventually whilst working away at their larger goals. I doubt they care who rules - I think their plans are larger and far worse than ruling the world.
Ethniu likely would have challenged any new Power. I have speculated before on who might win that and it's quite hard to judge. I can't see Cowl and Ethniu working together (unless they already had been...which is possible, if not likely). But would they have stayed allies? In theory Ethniu all armored up and with the Eye of Balor should be stronger. But the way it's worded in
Dead Beat makes you think that Cowl would have been stronger. A dark god of necromancy, likely. Easily able to make his own army I think. I suspect he would have had the power to pierce through the armor, given the requirement to get through Titanic Bronze is either enough power, or power from the right place (infernal or celestial). I don't see how he would counter the Eye, but Cowl is very clever and might have planned for such a thing. More likely he would have avoided a straight fight if possible and tried to work with her to suppress the mortals.
Which then gives us the mortal issue. Would Cowl have been strong enough outright to dominate all mortal opposition? Armies of the dead might suggest that, in a zombie apocalypse type way. One only has to watch a few zombie movies or tv shows to see how quickly civilisation would crumble - although mostly infection seems more dangerous than merely being summoned. Not sure how humans would deal with spectres like the Corpsetaker summoned. But humans do have other organisations that protect them like the Librum Bellum - the MIB. One expects they wouldn't have just rolled over, and might even have strategies for just such an event. Not to mention, we have seen that Alfred can probably handle even very powerful entities if he's close enough (although he still needs the Warden to help bind them). And that's just one thing - who knows how many other such countermeasures exist.
Yet Dresden, and the Wardens, the Necromancers and even Fae all seemed very convinced that should a dark god emerge, that was it for civilisation. This suggests it would be a far worse event than most, a being perhaps far stronger than Ethniu. Which might mean such a creature might be a lot harder to stop. And maybe not such a junior-league god, as Dresden thinks.
One wonders how the Outsiders would have dealt with it too. My guess is that just like with Ethniu, Cowl succeeding at the Darkhallow was merely an opportunity for the Outsiders to exploit. Creating the right kind of conditions for their version of the apocalypse. In the end, I think the Outsiders are ultimately the biggest threat to everything given they torture and destroy and consume universes, and want to do that to the entire multiverse of Creation. Or so it seems.
But it was still a really big event, should it have occcured. And I highly doubt that Cowl won't attempt another Darkhallow (although one thinks he might want to pick another city, just logically). Even the name Darkhallow (Dark-holy) gives you an idea of how big an event it was. Something curious we have seen (only briefly) is the power of holiness, or unholiness as the case may be. The Sleeper managed to consecrate the ground of it's Church. Normally, this is reserved for the White God and other major religions (I assume). Presumably, each of the varying religions in their era had this power too (Greek, Roman, Norse, Egyptian, Japanese, Sumerian, Chinese, Irish, etc) but due to current circumstances do not have this power any more. Would Cowl have had this power? Could he have consecrated his own special areas?
Food for thought.
In any case, do you think we will see another Darkhallow attempt? By Cowl or some other? Even Kemmler (should he somehow return, assuming he hasn't already)? If it occurs again, would the BAT kick off?
