If you’ve been following my story, you know I ended up missing the PAX Prime DM Challenge this year. This article is the third in a 3 part series detailing the encounters and maps I built. You can read Part 1 here and Part 2 here.
When I was working up my trap ideas, one of my first ideas was for a room with a switch that inverted gravity causing the party to have to fight on the ceiling and floor. While working out the mechanics of how this room would work in 4th edition, I had another thought, What if the entire room was spinning like the rotating corridor in the movie, Inception? How could I translate the mechanics of a rotating room into 4th edition and make it immediately understandable?
I’ll give you a quick rundown of the map then walk you through an example encounter in the room. The idea is simple - an encounter in a trapped, spinning hallway. Each round the corridor spins 90 degrees counterclockwise. For the rest of this article, “floor tile” refers to the tile that is currently in the normal floor position. At the beginning of each round, a new tile is placed to the left of the last floor tile. When you have placed all 4 tiles, you move the right most tile to the left side of the map. This simulates the revolving action of the corridor.
The spinning of the room introduces some constraints on movement. Each player needs to end their turn in a square on the current floor tile or fall prone in the closest floor tile square at the end of their turn. Also, if the creature passes through any trapped squares while falling to the floor tile, they take attacks from any trapped squares along the way.
I tried to keep the traps simple. Iron spikes randomly shoot up through the floor on the spiked squares. If you want to simplify the operation of the map, you could simply have creatures take 10 damage for each trapped square they move through.
Treat all the pit squares as normal terrain. If forced movement sends a creature into a pit square, they get the normal save or fall prone. You can even allow characters to stand and move in pit squares when their sides are aligned with the current floor tile. Don’t forget the extra height if a character fell from the bottom of the 20′ to the opposite floor tile.
A map like this could easily tear your players (and monsters) to pieces even without combat. Make sure to leave some sort of refuge area in your maps. On my map, the last 2 squares at the far end of the hall are the refuge spot. There is only a 10′ pit trap to mess with the players. The grates on the ceiling are also a place of refuge. Characters can hold onto the bars with a moderate athletics DC while the room continues to spin.
You also need a way to disable the spinning room. I was planning to run the encounter with a control panel on the far end end of the room, but you can place the control panel anywhere you like. The bottom of the 20′ trap is a particularly evil place to put it.
Running The Encounter
The traps in this room can be avoided pretty easily. Let the players move through a single revolution of the room to get acclimated to the physics of the area. Then, up the ante by adding monsters. I used my King of Monsters content winner, the horakh and a couple spider swarms. They both have spider crawl to further frustrate our intrepid dungeoneers.
The players enter the room and the door slams shut behind them. There is a large 20′ deep pit, several deep holes on the walls, and grates on the ceiling, but nothing seems out of sorts.
A loud chunking sound reverberates through the hall and the floor suddenly lurches beneath the players feet. Spikes shoot from the walls and the room starts rotating.
The room continues to spin. The players are now standing on what was previously the ceiling. A player spots a control panel on the far wall with his passive perception.
The room continues to turn and new traps spring up. A number of horakh and spiders flood into the room through the grates. The players divide up taking different routes through the room.
All tiles are now in play. Now the rightmost tile is moved to the leftmost position. The tiefling warlock fell prone because he didn’t end his movement on the floor tile.
More fighting. The tiefling stands up as his move action and attacks. He is going to take another tumble at the end of his turn.
OW OW OW OW!
The warlock double moves and spends and action point to get out of his predicament. The human wizard rushes to the ceiling grates and grabs on for dear life.
The tiefling copies the wizard and grabs onto a grate.
The battle continues to roll forward. One of the spider swarms clings to the ceiling and chews on the wounded warlock who is hanging from the ceiling by his tail.
The encounter continues. I wish these poor bastards good luck.