“ A modern kingdom still strictly adheres to ancient traditions due to their long forgotten deity getting annoyed at the moral decay, appearing as an AI Singularity and forcefully correcting everything it sees as morally wrong. As such, even though the weapons and technology have improved, the culture hasn't.”
“ 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...”
“ He's a non-descript man, with his pushcart. On it he sells nothing more exotic than jars of sun-dried tomatoes in oil and pickled vegetables. But he's always out there, in the courtyard of the great Guild of Wizards, in most weathers, and he'll have a kind word for you, and a jar.”
