This is a system for balancing magic based on two negative aspects: A) Magic creates “noise” that those sensitive to power will notice and B)Magic is channeled through rifts to other parts of reality OR other dimensions/planes/what have you and those rifts can get out of control…
They were a very religious people, focused upon their leaving to the afterlife. They associated magical spirits/ gods with birds. It is difficult to determine if this was metaphorical or actual.
Firearms & Artillery rules to simplify the addition of such weapons into a campaign setting.
Golden tablets with the seal of the ruler that issued the pass and the seal and name of who it was issued to. About the size of your palm of solid intricately etched gold. The holder of the tablet is backed by the authority of the king to make any required purchases on credit or enter any place they deem necessary. A very powerful token indeed.
With a huge number of sacrificial victims, another realm long ago secretly bound a Prince of the land spirits, Iorstonn by name, thus ensuring the fertility, and improving the magical defences, of their realm. But binding that Prince to one spot has disrupted the weather and magical patterns (ley lines?) over half the continent. Things have become bad enough that a coalition has been formed to rectify the situation, once divinations have established the cause.
Your party is one of the teams assembled to do the rectification: find the binding object and steal it ("so that we can destroy it here in our realm, of course"...*) or destroy it over there. Presumably the Prince will be grateful to his rescuers and angry at the binders, but with a greater spirit like Iorstonn one can never be sure: such beings are "tricksy".
* Of course, the rulers of our realm might want to control Iorstonn for their own ends...