Here's another video in our speed modeling series. This time it shows special human structure - Engine.
It is basically a step-on-it activated elevator, which transfers you up to otherwise unreachable places. In future it should be useful help for building an elevated base as well.
However, even if the middle part goes up, the cover around motors remains on the ground, so you'd better defend it carefully, unless you don't want to watch a slightly different version of Newton's gravity law (you know, apple on the head equals gravity) including motors and an alien forehead.
Engine - speed modeling (link)