This is an idea for a weird setting I had a few days ago. It's still rough around the edges, but I believe it's the perfect dump, for every dungeon, map or adventure idea one might find without having an immediate use for. Just place it in a destroyed world put it along the way ...
Basically it's a travelling mega-dungeon.
The Infinite Caravan travels the shards of the shattered universe. They say it's beginning is the end of all things and it's end is the Great Nothing at the edge of time itself. People cling like parasites on this endless procession of single-minded giant creatures, building houses with gardens on their backs and tunnels in their thick hide. No one knows where those strange beasts of burden came from or where they are headed, but some say they feast on the misery of dying worlds and all agree that it's the last journey of existence.
Scavengers of the Infinite Caravan
The stories how passengers of the caravan came to be on it are as manifold as the diversity among those travellers. All imaginable kinds of creatures, in a variety of cultures, languages, magic systems and high tech, all jammed together, building gangs and loose alliances, cults and armies, families and tribes, fighting every day for that square meter more. And yet they are united by one single motivation: the struggle for survival stands and falls with the very existence of the caravan. So as they venture forth under an ever-changing sky and scavenge the scourged lands of those worlds the caravan passes through and defend what few possessions they've left against hostile neighbourhoods, scared gods and entities that threaten to destroy the entire caravan, they fight for everyone stranded with them on the backs of those giant beasts.
They might scavenge for days and the caravan moves on, but will never end ...
Stay tuned for more stories about The Infinite Caravan!