Corner Cutter (Trap idea)
Here's one for you DM's that want a trap that can harm those players that like to stick to those corners. The players are peaking around corners for one reason or another, & every so often when they go to one, they will hear a slight *tick*. After establishing that this is natural for corners in the area that the players are in, one of the corner *tick* will should allot loader than the others. Soon enough, an axe will fall towards the person who stood on the ticker. Make the person who is standing there do a dex check, & on a fail, they will take 2d6 +2 damage.