How to Build a Troll Trap in Minecraft

block of your choice(i used stone),bait(an ore,like diamonds),sand,and signs.

build a simple house with no roof and a entering hole.

add your bait of choice at one of the back corners.

put a sign on your bait and put a sign on that sign. the second one shouldnt have a stick.

make a fuse of signs to the top of the house and make a roof out of the signs.

put sand on top of the signs so they can cover the player.

the signs are build together. so destroying the bait will destroy the signs too. and whatever sand goes up,must come down! crashing down on to the player suffocating them!