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The Corpse Mill

The adventurers stare into a dark cavernous room. In the distance they hear the grinding of stone quickly dragging closer. A massive wall slides across the open passage way entering the chamber. 6 seconds pass, and another wall grinds by. Every 6 seconds, the pattern repeats.

This room is considered a complex trap and requires that all the players roll for initiative.

Details:

1. The Mill

The spokes of the mill are walls that stretch from floor to ceiling, leaving only enough gap for tiny creatures like rodents or insects to hide in the cracks of the cobble stone, and have the wall pass over them safely. These spokes are spinning counter-clockwise at 90° every 6 seconds. The room has an initiative of 20. On the room's turn, rotate the spokes 90°

All players inside the circle on the room's turn (or that attempt to travel clock-wise) get hit by the wall. Move the player's token on the map to the next 45° spoke on the map.

The map on the next page is color coded to show the three zones of varying danger. The red zone is where the walls are moving their fastest, and they deal the most damage. The green zone is where the walls are moving their slowest and is the safest area in the circle. The yellow zone is a middle area of speed and danger. If a player is hit by the wall, the effect varies depending on which zone they are in.

Getting hit by the wall

Zone Consequence Red Creature must make a dexterity saving throw DC15. If the creature is blind (by not having darkvision or a light source for example), they roll at disadvantage. On a failed save, the creature is knocked prone, and takes 4d10 bludgeoning damage. On a success, they remain standing and take half damage. Yellow Creature must make a dexterity saving throw DC13. If the creature is blind (by not having darkvision or a light source for example), they roll at disadvantage. On a failed save, the creature is knocked prone, and takes 2d10 bludgeoning damage. On a success, they remain standing and take half damage. Green Creature must make a dexterity saving throw DC11. On a failed save, the creature is knocked prone, and takes 1d10 bludgeoning damage. On a success, they remain standing and take no damage.

2. Trip Hazards

At both the top-right corner of the room, and bottom right corner of the room is a small crack just big enough for a small creature to fit through. Behind the crack is a small cave that connects to the 2 safe pockets at the top and right of the map. Those entrances are also too small for a medium creature to enter. Behind the cracks that face the mill is one kobold each with a bola or net.

As soon as a player is within range from the crack, the kobold throws the bola, and hides. The player can make a DEX save (DC13) to dodge the incoming bola. If the player is blind (because they lack darkvision or a light source), they roll at disadvantage as they hear the spinning bola incoming, but can't see which direction. On a failed save, the player is knocked prone.

3. Safety

On the top and right side of the circle, there is a small 10x15' pocket where a creature can stand and not be in the way of the rotating walls. On the bottom of the circle is the 15' wide entrance, and on the left is the 15' wide exit making there a safe place to hide every 90° or 60ft.

4. Loot

In the first safety pocket on the right side of the map is a small stash of kobold supplies. I gave my players, a speed potion, some poison and some health potions, and an enchanted sling, but you may find something more fitting. Inside the small caves that the kobolds are hiding in is a good place to hide some supplies too. Maybe some ammo or rations. I never intended the players to look inside said cave, but if your party is all gnomes and halflings, they very well might.