Who is Gareth?
by Hervé MusseauAnother possibility hinted to by WotI and the PWAs is that Gareth may be an Old One.
The tricky part is, before we can see what it implies, we must first determine WHAT is an Old One.
a. Old One is another term for DM
This was probably what was originally intended by the designers of the game. There is nothing more powerful, game wise, than the Immortals [though you may consider the Powers of AD&D more powerful IYC], and what's beyond are the DMs - the only beings that can do more than mere Immortals, as they can alter reality, kill Immortals, or even make all reality to stop by no more playing D&D!
In that case, Old Ones are just a myth for the Immortals, with no game reality. The Old One that appears at the end of WotI is an alias of you, the DM, or of Aaron Allston.
And if Gareth is also an Old One, then it's also your alter ego directly altering the world (or Ann Dupuis'). As the DM is almighty in his campaign, then Gareth is too. Dot. And he does exactly what wish...
b. Old Ones are the Dark Powers
This is based on Marco's work "Ravenloft and Mystara: A possible (frightening) connection." I also think someone wrote a scenario of an old war between the Dark Powers and the Immortals long, long ago, ending with the Dark Powers being imprisoned, though I can't find the original post.
So there are Dark Powers that have huge powers, maybe even greater than the Immortals', but they were banished to another dimension long ago (similar to the Carnifex). Immortals lost knowledge of this war and the Dark Powers, and have begun to suppose the existence of the Old Ones, whose powers would be to theirs what theirs are to mortals'. The Old Ones live in the Vortex Dimension, protected by the Vortex. What the Immortals do not know is that the Vortex is also called the Mists, and that the Vortex Dimension is just another name for Ravenloft... The Dark Powers are trapped inside and can normally not do much except swallow people and places into the Lands of the Mists. But one of them has somehow managed to escape, or to have a part of him (an avatar?) escape the Vortex and roam the Multiverse...
In that case you have an Entropic-like scenario, just even darker. The escaped Dark Power's goal is to complete the process of freeing himself from Ravenloft, and/or free the other Dark Powers so they can reclaim the Multiverse for their dark ends.
Why did the Dark Power appear before Ixion and Rad at the end of WotI and stopped the war, when his goal should be to bring chaos? Well, the NoS is a key to freeing the Dark Powers! When Rad activated it and caused the WWM, this Dark Power escaped. However, it was insufficient to completely free him/them all. So he arranged for the NoS to become tied to the Sphere of Entropy, because only thus can it create the gate/whatever that will free the Dark Powers from their prison. Why did he say, as Gareth, that he had returned from the Vortex? Well, two possibilities: either he knew that the Immortals would assume he's an Old One and fear him, or he was just content to say that he had escaped from the Mists and is announcing the return of the Dark Powers (the Immortals' fault if they have lost knowledge of what this means). Why did he start the cult of Gareth? For two reasons: First he needs some mortals to do his bidding, especially handling/activating the NoS when it's ready; second he's making ground for the upcoming war with the Immortals by sapping their power base, i.e. mortal followers; maybe he even believes that these mortals will serve the Dark Powers when they have destroyed the Immortals, as they do in Ravenloft.
c. Old Ones are powerful beings just as in the Immortals' theory (i.e., classical theory about the Old Ones) Then, they are very powerful, created the Multiverse as their experiment, and more. If they are so powerful, why would they (or one of them) intervene, when they could simply alter what they want?
c.1. Gareth wants to show the proper path Gareth is a good Old One, as they are all, and saw that the experiment was not going the good way. Rather than simply wash away this failed experiment, this Old One (with or without the agreement of the others) has decided to put it back on the right tracks. He thus intervened at the end of WotI, showed Immortals how bad they were behaving, recharged the NoS, and made of Rad a new experiment to see if he could change his ways.
Then to make sure that the proper way would make ground, he created a new Immortal or assumed an Immortal identity, and preached a new way (as Gareth).
c.2. Gareth is an evil Old One
Not all Old Ones are good, there is a balance here as everywhere else. Old Ones are to Immortals what Immortals are to mortals, and they lend power to the Immortals in the form of access to the five spheres. As a Multiverse becomes more attuned to one of the spheres, Old Ones that are aligned with that sphere gain power. Old Ones normally cannot intervene directly in the Multiverse. But this Entropic Old One has decided to bypass the directive (as some Entropic Immortals sometimes do on the Prime) in order to gain more power for himself and his sphere. That's why he turned the NoS into an Entropy artifact, and he's now posing as a good Immortal to wreak more havoc (as per Gareth = Loki).
c.3. Gareth is a rogue Old One
Old Ones vary in characters, and this one has decided to intervene himself in the experiment even though it's forbidden, because he thinks that will be fun. He does not really want to harm (although...) but just wants to meddle with the Multiverse experiment. Other Old Ones may or may not be aware of his actions.
This scenario is an analogy with Q and the Q Continuum.
In an episode of ST:TNG, Q is stripped of his powers by the Q Continuum and must live as a mortal. If you push the Q analogy that far, you can have Gareth be stripped of his powers by the Old Ones after he intervenes in the Multiverse in WotI, and so he MUST assume the id of an Immortal. Maybe he was aware of the punishment he could have before he intervened, or not. Now he must redeem himself to become an Old One again, and accepting to be an Immortal (and thus creating a new faith, gaining followers etc) is part of the process.
d. Gareth is an Old One that
abandoned his status Just like Immortals can become Old Ones by
dropping their status, starting back from the bottom, and then
rising again, so can the Old Ones. An Old One who has mastered
Hierarch Old One status may decide to give it up, and start again
as a mere Initiate in the Multiverse, and when (if) he becomes an
Hierarch Old One, he becomes what comes next [some people on the
list have said it becomes an Very Old One, some said it's a circle
an he becomes a simple mortal]. Since he claims that he returned
from the Vortex (which is literally true), he must have retained
some of his memory (contrary to an Immortal becoming a mortal).