Post-Apocalypse Dungeon Crawl

The Dungeon Crawl. Staple of Fantasy Gaming. Enter an underground complex, and raid it for XP/Loot. They can vary from very small (One Page Dungeon) to very large (The Underdark). But how can they be incorporated into a Post-Apocalypse setting?

Ruined Cities are often featured, but focus more on Interiors than Underground. Carefully negotiating rubble-strewn streets to reach Storage Depots, Warehouses or other Loot Drops. With possible snipers on rooftops, the grey/red/<insert Apocalypse here> sky always in view, and many exits, they don’t really have the same feel.

But what if the City IS underground? Not originally-underground, but became-underground. I’m thinking something like Manhattan getting hit with a bigger version of Pompeii’s pyroclastic flow. The streets are filled with rapidly-solidifying ash, covering over 20-stories deep! Buildings are preserved, but access becomes limited. Maybe a lot of the Flow doesn’t penetrate much into the buildings. The rooms are still rooms. And there is Loot to be had! Pre-Fall Loot!

Access would be through the tops of tall buildings (now low buildings with Dungeons beneath!). Areas between buildings is blocked by ash, but could be tunnelled through (and possibly already has!), although the top layers are baked solid, and excavation efforts are hampered by bandits/mutants/radiation/<insert reason here>. Who knows what foul creatures reside in the deeper levels of such places? Mutants with pig-like noses and penchant for cannibalism? Animals escaped from the Zoo, twisted over generations (because Apocalypse)? Rodents over-gorged on food-stores and grown to Unusual Size?

With short sight-lines, melee combat becomes favoured over sniper shots. You’ll need to bypass locked doors and vaults. Maybe previous occupants have laid traps. As this is an expedition away from Base Camp, a medic will be useful.

I’ll be expanding on these thoughts later, but I present this as a taster.

Feedback Appreciated.