The Irritation Trap

This trap is an anti everyone trap.It's also very irritating.

Step 1:

Build a 3 by 3 square with pressure plated on the outer blocks.Leave a space in the middle.

Step 2:

Place a piston next to each of the planks.

Step 3:

Place 3 blocks in the centre going up.Then place slabs all around those.

Step 4:

Destroy the 3 blocks and replace the top one with a slab.

Step 5:

Now when you walk in, there's no way out.Congratulations!