A while back I ran a flooded dungeon for a group of sixth level characters. The concept was simple, at the heart of a marsh was an ancient temple in which was a crown. All the players had to do was collect the crown from the temple’s treasure vault and return it to its ‘rightful’ owners.
But I am a stinker and decided to make the temple a bit more difficult. So I had it subside into the swamp, and not evenly either. One half was lower than the other and most of it had flooded to one degree or another.
So, it was full of muddy swamp water that gets deeper as the players approach their goal, the treasure vault. Key features included:
- Slimy, slippery surfaces,
- Water that stank and you couldn’t see through,
- Rotting vegetation causing build-ups of highly-inflammable methane that got caught in pockets,
- The constant risk of collapsing ceilings and floors,
- Native fauna including giant marsh crabs, venomous swimming serpents and piranha
- The main protagonists were savage mandrills whose leader was wearing the crown (no it wasn’t in the vault after all – as I said, I am a stinker) and as a result they had all become more intelligent and cunning,
- An aggressive and territorial, ginormous crocodile (so big he could not fit in some rooms),
- And finally a few still functional stone traps.
Within minutes of entering all the characters were slick with black, stinking mud and having to work out how to cross floors that were wet, slimy and listing at fifteen to thirty degrees. As you might expect they didn’t bring nearly enough rope, pitons, torches or other spelunking supplies.
The marsh crabs had no problem with the topsy-turvy environment and seriously threatened the party until driven off with fire. A henchman was lost when a stone pit trap lid opened under him, dragging him down into its watery depths. Fortunately he didn’t drown as the piranhas killed him long before then.
The Mandrills delighted in dropping masonry on the characters, especially as they tried to flee the crocodile. The mage was paralysed by a viper bite and almost drowned face down in six inches of water. The rest of the party being a little busy fending off a guardian stone golem (didn’t I mention that?).
The Paladin lost his eyebrows and roasted the party thief when he lit a torch in a dark chamber full of methane, causing said thief to slide slowly down the angled floor into the open jaws of the crocodile, munch. The party did manage to recover his body from the crocodile’s belly after he had been swallowed whole.
They eventually achieved their goal by killing the Mandrill King and escaped over the roof. Not one character had double figure hit points. Two were infected with and unpleasant necrotic disease that took a High Priest’s ministrations to clear. The thief left over the shoulder of the guilt-ridden paladin, who spent his entire reward having the poor wretch raised.
When they levelled up all the players paid more attention to putting ranks in their climb, jump and swim skills.
In preparation for all this I drew up a simple map of the Temple as it would have been in its hey-day. I even marked on statuary, pillars and large items of stone furniture. Then I made a copy and got my coloured pencils out. The players received a copy of the original from their patrons.
I decided which side had sunk and began shading in the rooms and passageways in shades of blue. The darkest blue was for the chambers that were totally submerged, such as the treasure vault, then lighter blues indicated half full, quarter full, damp etc. Larger chambers and longer passageways were shaded progressively across their length showing how the water got deeper the further you went in.
All the movable stone furnishings and statuary was moved down the rooms so it ended up in jumbled barricades across the bottoms of the rooms (and often across important doorways).
I drew a handful of simple diagrams showing stick figures trying to stand upright on floors at increasing degrees of tilt, to show the players the environment they were having to cope with. It was my idea that the deeper in the swamp the rooms were, the more they had tilted. This would mean that in places the flooring had cracked and was angled upwards causing more fun and games.
I also marked a few holes in the temple roof and the rubble this caused below. The mandrills used these as places to watch the characters and to ‘assist’ them by dropping slabs to use as stepping stones. One slab squished the party cleric and the others had to pool their dwindling healing supplies to save him.
Different parts of the temple were numbered to a key that told me where various monsters were. For example the piranha were only in two chambers and one pit, and the crabs lived in the shallower water by the entrance. The crocodile travelled around a lot and I had him appear at narrow doorways he couldn’t get through to menace the characters before disappearing back into the gloom.
I’m thinking of doing a version of the Poseidon Adventure in the near future if you want to play….?