The Wave

The sky turns red. 
A distant hum becomes a maddening whine. 
Something is coming. Get to shelter, quick! 

A quick supplement for Vaults of Vaarn's Summer Jam, I wanted to adapt a niche concept I'm extremely fond of from a favorite game into something that can shake up your players' traversal of any science fantasy setting. 

Inside you will find an existential threat to any party and a reason to explore the ruins of the world for answers. 

Good for DMs who like to stress their players out during overland travel or people who just like cosmic levels of scientific peril.