[@Riffus Maximus] Let me try and break down your questions as best as I can.

[quote=@Riffus Maximus]
Is it known to the characters why this entity is named Chaos? For a being whose apparent purpose is to conquer all under one rule, it kinda feels like it would unify this whole mess of planes into a single banner. Would it be far-fetched for a character to believe Chaos' design is one of true order?
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They probably don't know why Chaos identifies itself as such, though they could guess at it. The theming is more like a "prima materia" type of Chaos, if that's helpful. What I read about your character's motivations pretty much works, people can easily project their own intentions onto Chaos, it's not very... forthcoming, nor personable.

[quote=@Riffus Maximus]
Is it possible for a plane to host more than a single shard of chaos? Does these shards bring some sort of knowledge about the master. Does Chaos have an actual physical form? 
[/quote]

It's one Shard to one Plane. The Shard's presence on the Plane is what shattered it in the first place. Taking possession of the Shard brings you into communication with Chaos. It's like picking up the One Ring, but Sauron wants you to use it for him. The physical manifestation of Chaos is Gladius, which I mentioned briefly. It's like an evil, shapeshifting fortress that can manifest itself on new Planes. Every time a Shard is acquired and reintegrated with the Heart of Chaos, Gladius grows larger and more complex. This is also the process that reunites the Planes.

[quote=@Riffus Maximus]
For the long-lived races, just how long ago was Creation shattered into pieces, just to not overlap a character's age with the creation of its homeworld.
[/quote]

As I said before, each Plane has a unique relationship for time. For some, the shattering was many thousands of years ago. For others, perhaps it was merely hundreds. What they all have in common is that the shattering has passed out of living memory, so however long it would take for your elder race to have forgotten it, that's how long ago it was.

[quote=@Riffus Maximus]
Is it possible to play more than a single character? I've seen something about using the character's homeworld ressources to their disposal, so I guess it would be likely for the characters who are more of leader types to bring their generals and subordinates from their conquered homeworld into others, unless the Archons are only able to travel alone?
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Only one Archon, but what you're describing is my intent for more leadership focused characters. I think I'll include a section for this on the updated CS. Until you acquire a Plane's Shard and reunite it with the others, you're limited to whatever resources you could fit into Gladius with you. Which could be considerable; I am thinking about adding a section about Gladius onto the CS, so you each get a "wing" to personalize.

Anyway, regarding your character: I think she is good, with the only nitpick being that nobody should even really know that there are other Planes out there until they get their hands on a Shard. 

[@Sniblet] I was pretty much fine with your character until you pointed out that you ported it from a video game. For that, I would ask that you personalize them a bit more? Maybe introduce more of a personality to help them interact with their fellow Archons? Otherwise they may have difficulty cooperating with your 40-million-year-old "elder spirit." Have you considered maybe that they might have been human to start, until learning the "truth" within the Book of Light?

Interesting association: Chaos' symbology associates with with "darklight," a light and darkness that coexists. Kind of a Yin-Yang thing going on.