Ancient of Days

Ancient of Days is a Power - one of the godlike rulers of both the Material Reality and the Elsewheres. Like in the case of other Powers, it's unknown how exactly it looks. It isn't even known if it actually 'looks' in conventional sense, being a concept itself more than anything else.
The Lightbringer is primarily a solar deity, that in the past was also to certain degree associated with rulership. In the end, though, it's a deity of splendour and glory associated with high position more than of actual governance (as that's a domain more closely associated with the Ancient of Control.
Perhaps due to the way the celestials look like, the Ancient of Days is typically portrayed in art as an androgynous human-like entity, with multiple sets of feathered wings on their back. This has no relation with Christian portrayal of angels and, in fact, was encountered even in the cultures that never had any contact with the abrahamic faiths as a whole.

Divine Symbols & Sigils

Solar symbolic of all kinds, also colours of gold and silver.

Tenets of Faith

The Ancient of Days is generally considered to be one of the few Ancients that are morally neutral rather than to even the smallest degree of malevolent. It's hard to overdose on sunlight (aside from getting sunburns), to begin with - in exchange it's also not easy to amass its attention through ways that aren't casting magic. As a result, cults of Days are comparatively rare.
Many of them are also closer in theme to actual religious organizations of the mundane world, often borrowing a lot of aesthetic from conventional religions (like Christianity, ancient pagans - especially Roman - and various eastern religions). In fact, hearing a pastor/priest/else of some small religious off-shoot beginning to involve solar metaphors in their sermons is typically a flashing red warning sign.
Cults of Days are, typically, considered to not be particularly harmful groups. To summarize the situation, they are only as dangerous to people around them as a mundane world cults/religious organizations. As a result, some of them are actually tolerated by local mages, for as long as they do not develop ambitions too large in scope.

Summary

Type: Power
Pantheon: Ancients
Aliases: False Light, Sun Everlasting, Lightbringer
Alignment: Neutral [VIII]

Aligned Entities

Aberrants:

Demihumans:

Celestials

Aligned Spells

Lore of Days