I really like the idea of the Rod of Seven Parts, the ur-artifact from D&D’s past. It has so many good nouns! The rod-wrights, the Wind Dukes of Aaqa, and their surviving artefact, once-known as The Rod of Law. The victim of the rod, the lieutenant of the Queen of Air and Darkness, Miska the Wolf Spider.
But that’s not the only piece of world-shaking technology floating out there; there’s lots of other artifacts. What’s interesting about the Rod of Seven Parts is that it was purpose built as a weapon in an ancient war against a specific foe, and therefore it’s a cultural artifact. Yes, we can see the Wind Dukes as a semi-divine organization, but they’re still “only” djinni, they’re not, like, Empyreans or Solars or demigods or something. Arch-djinni, at the outside.
And Djinni, relative to our other creature types, are not all that organized! In my campaign, the giants are unified albeit city-state-y and not that magical, the efreeti are certainly a burgeoning economy; the elves are post-apocalyptic but had hit efreet-relative heights, the hebdomad of angels certainly has this on lockdown. And then there’s the command-economy of the Iron City.
My point: there’s a lot of creature types with access to the organization, magico-technology, and stability necessary to work on these long term projects. And to be clear, by this I mean crafting artifacts. And by crafting artifacts, I mean good ones; stockpiled rings of wishes, as many as possible.
Picture it. You’re the First Planetar of the Eastern Gate; you wield a radiant sword in the service of the Seven, keeping watch over the Paths of Flame. And you are the first to see a movement beyond the many-hued veil; the servants of the pit and prepare to storm the gates. You sound the horns of alarm, and ancient plans of defense are set into action. But we’re talking astral beings here; they don’t use catapaults loaded with stones or iron-barred gates. They can’t; their foes teleport and phase, fly and shrug off elemental energies. They need to store potential energy against they day they need it, but their armories aren’t mortal. Your duty sidearm is a shard of the holy presence itself, by the seven! No boiling oil for you; the fire wouldn’t do enough damage and the oil is so déclassé. Instead, holy water would make sense, and presumably the industrial-strength equivalent even more so. Maybe the whisky equivalent of holy water — water of life? — maybe the alchemist’s equivalent. And that’s only good against fiends and undead. What if they use giants as shock troops? Presumably Heaven is better prepared than just moistening the invader.
In a long-term war with a known enemy, each faction probably has its Rod-equivalent. Hell and Heaven have been at war for literally longer than humanity has had fire. They’ve got to have an upgrade by now.
But is it a genetic ability shared across the race? Is it issued to every footsoldier? There’s not a great reason to say that each and every Glabrezu can cast wish, but there’s every reason to say that each and every Glabrezu can put a summoner in a position to get a wish, if they are willing to sacrifice enough and lucky enough. Ditto efreeti. Ditto djinni. The societies of which they form a part has access to powers, and the members are an introduction to the movers and shakers.
Let’s talk efreeti. Like Rakshasa, they lair within the Burning Azoth, a formless place of energy, form and seeming. Creatures exposed to the azoth which survive are the spellburned, permanently changed by that exposure. It is said that in the moment of the spellburn, one speaks to Azoth Itself, the will of magic; one can, in that moment, achieve a wish. Efreeti, Rakshasa, and others often harvest azoth, storing fulminating casks or lyrium stones in their keeps. Exposure to these lesser forms often grants the effects of a variety of potions or a pearl of power that forces a wild magic surge. The occasional explosion is a low price to pay.
Devils are much more structured. Their mastery of nine worlds and colonies on another hundred, combined with their infrastructure and organization means that if you name it, it seems likely they can produce it from somewhere. They don’t live in the Burning Azoth; they live in their worlds and in the gateways between them. They have enormous libraries of forbidden knowledge, every spell they have ever managed to trade for, interrogate out, or create themselves. They have archives of creatures, imprisonmented; they have archives of objects, protected from theft and scrying, and they have gates aplenty. They also have several well-documented highly magical leaders; Asmodeus who is nearly a god, Mephistopheles, Glasya, the Hag Countess, Dispater, and no doubt others. I’m sure they’ve kept the souls of a thousand generations of archmages on tap, as well. As a result, there’s very little they can’t arrange to have happen.
The Djinni and Empyreans and Storm Giants and Elves, by comparison, are punters. I mean, cloud castles, bottled lightning, and so forth. But wish? Unlikely. A few legendaries, that’s it.
The angels… well, nobody knows. It is known that they have rings of wish, that the very terrain of the heavens is blessed. But it’s not clear what the upper limits are — and the devils claim it’s flummery, and that the angels are stretched quite thinly indeed.