And that filters down to ardlings, tieflings, and aasimar - ardlings are the descendants of celestials, tieflings are the descendants of fiends, aasimar are the descendants of the divine and their angelic servitors.
Right. Tieflings descend from any Fiend. It is a technical possibility, this particular Fiend might have a Good alignment, but still be a native of a Lower Plane.
The following distinction I didnt catch earlier:
You want Ardling to be the counterpart of the Tiefling, thus descend from any Celestial.
However. You want Aasimar to specifically be a descendant of a Solar (or similar Divine being)? This Solar may or may not be a Celestial.
Here is my thinking out loud while exploring this distinction.
Regarding Aasimar the proposal can work. Solar (and Planetar and Deva) are "Aasimons".
So, an Aasimar might specifically descend from an Aasimon, such as a Solar.
Notably, an Aasimar might come from a particular Solar that was created in one of the other alignment planes, and have nothing to do with the Upper Planes.
There are Good Aasimons and there are "fallen" Evil Aasimons. This is already a thing. An Aasimar can descend from any of them.
But regarding the Ardling, the Ardling concept is too specific to the GCG Beastlands Plane and its concepts like Beast Lords and humanimal versions of Guardinals. Even the Ardling flavor is a very narrow subset of the sapient animals in Beastlands. I dont think the Ardling can serve as descendant from each and every Upper Plane.
I think you're missing what I'm going for somewhat.
I don't mind the some fiends serving evil gods, but I've always liked that there are also large portions of them that very explicitly don't.
A "god" means something specific. It is a person who people "worship" and "serve", and specifically build "temples" to with dedicated "priests" whose job is to officiate over the offerings to the temple and any holiday customs relating to the temple tradition.
In this sense, a Greek dryad was and is a "god".
Whether a Fiend is a "god" or not, depends on whether communities are building temples and dedicating priests for a cultic rite to worship the Fiend as a god.
Some Fiends are more like mafia bosses, and there is no significant sense of "worship" happening, so they arent "gods" in any technical sense. But some Fiends, such as Lolth are "gods", namely objects of worship with temples and dedicated priesthoods.
In 5e, according to the official statblock, Lolth is the Fiend creature type, even tho she is also a god.
In parallel, any powerful creature of the Upper Plane is the Celestial creature type, whether or not any communities are worshiping the creature as a god.
- Most devils serve the Lords of Nine, and through them Asmodeus - who wasn't necessarily portrayed as a god until 4e, a decision I happen to disagree with.
- Most demons serve the various demon lords and demon princes - some of whom were also gods (Lolth, Orcus at some points) and others who weren't.
- The yugoloths are famously anti-theistic - the Wasting Tower of Khin-Oin is said to be carved from the spine of the first godling that ever made a deal with them.
Asmodeus behaves more like a secular mafia boss. But I think his ego likes it when certain Human communities in the Forgotten Realms setting worship him as a "god". No doubt he encourages this worship to help consolidate his power base in the Hells.
Officially Asmodeus is an "archdevil" and a "devil". I assume he has the Fiend creature type, even tho some Humans worship him as a "god".
Any creature that is native to the Lower Planes is the Fiend creature type whether a god or not.
The celestial side of the equations has always felt far more tangled up - particularly in Celestia, where it's sometimes hard to tell whether the tome archons of the Celestial Hebdomad are in charge or some nebulous selection of good gods.
In parallel to the Fiends, any creature that is native to the Upper Planes is the Celestial creature type whether a "god" or not.
What I'm proposing is that celestials (archons, guardinals, asuras, whatever replaces the eladrin in Arborea) remain the counterpart of opposing alignment to fiends as a category
Yeah, the Celestial creature type is ANY native of the Upper Planes, whether a god or not, and whether an archon, guardinal, eladrin, or not.
(Albeit, I would prefer to call all of these natives the Upper Planes the "Angel" creature type. Opposite Fiend, and instead of Celestial.)
but that angels split off into into a third category all their own that isn't explicitly tied to alignment, so that any god can choose to create/call upon angelic servitors, not just the ones that are arbitrarily put in the "Good" bucket for whatever reason.
There are creatures who ally themselves with or who serve under a powerful Celestial, whether this Celestial has worshipers or not. These are armies or bureaucrats or messengers or agents.
Going by earlier D&D traditions, these armies in the Lawful Good Plane are called "Aasimon", including Solar, Planetar, and Deva.
In the 2014 Monster Manual, the "Solar" officially lists as Lawful Good, now understood more clearly as "typically" Lawful Good, but perhaps should instead be "Any" alignment. So its alignment and mission depends on which "god" or other powerful being of Divine magic created it.
If Asmodeus wants to create a Solar to send it on a Lawful Evil mission, that seems fine enough. Even the earlier traditions include "fallen" Solars. So a Solar that was created to fulfill an Evil purpose in the first place doesnt change anything official.
If a Lawful Neutral Modron in Mechanus creates a Solar, that is fine too.
Celestials and fiends can still occasionally choose to serve a deity, but they originate via the natural processes of the Outer Planes as an expression of alignment.
Obviously, the choice to worship something or not is a personal decision and can be for various reasons.
The natives of any Upper Plane can choose to serve or not any powerful being whether worshiped or not.
Angels can occasionally choose to abandon their divine patron or fall out of favor and be cast out, but they originate as servants created by a god as expressions of a divinely ordained cause.
Definitely.
If Asmodeus creates a Solar to fulfill a Lawful Evil purpose, that Solar might well decide to help the Upper Planes of Good, instead.
Unrelated, if you want to drop "Hades" as the name of the pure NE plane of the Great Wheel, I'd say go back to using the Gray Waste - Tartarus is analogous to Carceri.
I know 1e referred to the Evil by Chaotic Evil Plane as Tartarus. I supposed that since 5e now calls this plane Carceri, the unused term Tartarus could be recycled for the True Evil Plane.
But you are probably right, Tartarus is probably still in use as a byname for Carceri.
So using the 3e name for the True Evil Plane, the Gray Waste, is probably the best way to go.
Renaming the True Evil Plane the "Gray Waste", helps avoid a new confusion in 4e and 5e, since "Hades" − the Underworld realm of the dead − makes more sense as one of the bynames for Shadowfell.
Waste is itself an adjective, such as in the phrase "waste products". But perhaps "Wasting" works better as a descriptor. Thus there are three kinds of Fiends, depending on which alignment plane they personify.
Fiend
• Lawful Evil
Infernal: Nine Hells
• True Evil
Wasting: Gray Waste
• Chaotic Evil
Abyssal: Abyss