“ A rather large armed group slowly walks the road. Unless you get to see what they transport, you could think it is a caravan with expensive goods, or the soldiers escort someone important. But this is a prisoner transport, on the way to mines, criminals on their way for punishment.
The soldiers may be willing to talk, the captain will have a few questions on you and the road, but they will keep distance, and part soon.”
“ 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...”
“ Perhaps the product of another universe or time, this vessel appears as an early Tall ship, but is made of iron from keel to spar. The sails are a battered canvas but are nearly indestructible, but in truth do little to move the ship - the ship is able to move even with no winds.
The ship is powered by life force, requiring regular sacrifices to ‘charge'. The victims are cast in front of the vessel as it moves, it's razor sharp bow bisecting them. The ship may initially be missing key components and the ritual to power it would also require research by would-be users.
The ship has no built in weapons aside from the bow, which can easily cut even large wooden ships in twain.”