FrankTrollman wrote:Powerful clerics have basically no reason to even talk to each other. Powerful wizards onl[y] have cause to talk to each other to trade spells. And that only needs doing once a century or so.
I see that being 100% true in any normal game. Totally self-sufficient and with no need to bring more people into the cleric club? Yeah, just wall yourself into a temple.
What I was thinking, and I could be convinced to change my mind, is that your powerful casters started off as cloistered nerds who had no idea what to do with their power. As the Empire put them to use they needed to train lots and lots of initiates to get as many
call lightning spells in the field of battle as possible. These guys formed fraternities and schools because everyone who wasn't a caster treated them like incomprehendable freaks and the organization made the training easier. As they rose in power these new initiates were forming a new society, and people heard more and more murmuring about how "Us sorcercers could really run the military campaign better than the generals, and we wouldn't need all those fighters at all!" Then later the newer recruits murmur, "Why do we need the Emperor anyway?"
Different schools tinker with tactics and find ways to exploit magic to gain previously impossible power. When a school of wizards starts summoning effriti for wishes, that school becomes able to destroy any rival in about a month. Then the secret of what they found they could do becomes both a force that bonds them and a threat - anyone who even hints at disloyalty is assassinated to keep the secret to their power secure.
Then they not only have trans-dimentional power, but political power. Other schools of wizards oppose them and find themselves obliterated, and soon the others cow. Anyone who doesn't get in line to back them in every facet of society is prevented from being a wizard practitioner at all.
As this happens a religious order of clerics discovers persistant magic and does something similar. Then the druids do it... etc. This all snowballs, during which time the most powerful among them realize that yeah, the whole material plane is irrelevant and so are the thousands of doofus rabble-rousing freshmen in the school. Why do they need an empire, much less a cook, a scribe, a house, or friends? They find out quickly though that wizarding is just easier when you have allies who can warn you when an assassination attempt will be made... if you tow the party line... if you pay your union dues and don't go making it obvious that their big powerful group just as irrelevant as it actually is. And this leaves them loads more time to do things like taking over whole planes and setting up new ones just to make yours seem less attractive for conquest.
Behind all of this is one basic tenant of an economy: competition. The casters may not need an influx of gold all that much since with enough power you literally can make it out of thin air. But nothing progresses when you do it the easy way, so magical services drives both the economy and the advancement tracks of casters. You don't want the only thing your school is looking to acquire to be hurt by another group competing with you; and as much as you might want to try fair competition between individuals, enough people don't want it that the unions make it impossible.
Then again, I might be basing too much of this on human history and society of the real world, and not enough on the magic system in place.