This little guy is made from only armor stands - its AI will follow you around using only scoreboard operations, so it's not your usual "acts like the built-in AI" mobs you'll usually see with command blocks. There's actually some fairly fancy maths going on behind the scenes.

This is part of a "vanilla mod" system I'm making, so I'm not going to provide any fancy way of getting it just yet. In the end in that mod pack it'll be craftable with a component you get from killing an elemental boss. If you want to play around with it, feel free to download the test world at the world download link though.

Oh, and for those of you who like stats - 238 command blocks, 27882 characters.