Minecraft traps

This is about traps you can make in minecraft so post in the comments traps you know of and/or know how to make

Trap 1: The Lie

make a small building and put a short hall to a cake at the end of it and hook a piston up to a pressure plate that should be infront of the door that goes into the hallway that will move the ground right infront of the cake and will cause the victim to fall to his/her death. the block infront of the cake that moves should be two blocks away from the door to work efficiently. NOTE: you can also put lava, TNT, void *if admin*, and mobs at the bottom of the hole aswell. also put in a sign that says THE CAKE IS A LIE at the bottom of the hole
from above: +piston -door Ocake =redstone ~random blocks _pressure plate *piston moved block .nothing
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might be hard to understand blueprints :/