Here is another installment of exTRAPaganza, our Thursday over-the-top trap series.
This room was used to make pastry and cut it into strips at scale.
The floor is made of marble, but an average Wisdom (Perception) check detects grooves that run the length of the floor from end to end about 6 inches apart the correspond with slits in the far wall.
One round after a party enters the room, the cutters come out of the wall. All targets in the room suffer a high bonus melee attack for heavy slashing damage. If they don’t leave the room out the other way the next round, they suffer another attack as the blades reverse direction.