Seeking Inspiration - Halloween Special

[domino]

Make them dreaming somehow. That way, you can do things like suddenly change locations, things around them, making the world they're in disjointed and inconsistent.

 

[Dragonwriter]

This will simply result in the PCs setting fire to the field. Or eating it. Perhaps both, at the same time.

While they're in it? This party doesn't seem like the type to be sporting several Resist Energy spells...
Of course, if they burn it rather than enter, it could just piss off the lurking monster. And whoever might own the field.

But if this is more like Persia, is it also a desert? If so, several of the ideas here would need some tweaking... Maybe a haunted cactus patch?

You could also use sand-burrowing things. Maybe take some inspiration from Tremors (the first one, not the latter entries, simply because the latter ones went well into the Comedy genre). Perhaps a Swarm-Shifting (Libris Mortis) Undead that turns into sand or dust, a la Imhotep from the 90's The Mummy.

 

[was]

Try hunting down a ghost pirate ship