Will edit this to include recent relevant information. Spoiler: outdated original post I invite you to try the following structures in creative mode, because otherwise you might not see what it is I'm typing about. Here is the basic construction: A player running from the left and jumping between these two little bits, will shoot out and not be able to come back in. Weirdly, it won't work mirrored, and the hole in the ground makes it significantly more consistent in letting players through. The hole in the ground is crucial. This is a one way door. It creates some interesting possibilities. Any player who jumps in through the gap will be trapped. In the spiked version, any player who jumps in vibrates back and forth between the spike and wall and explodes. The gold is just there to look pretty. Maybe attract a victim. You can also create a high speed elevator. With a tower like this, the bottom made so the player can enter from either side of the wall. This time when you jump and hold jump, you'll cannon out the top at something like twice the speed of a normal wall stair thinger. And exit at any point earlier by hitting left and going through the wall. Etc. etc.