So, I was fiddling with Marching Cubes and finally got to the point of making a much more efficient voxel terrain system that generates quickly and update quickly as well.

Starting map:


Added blocks (As you can see, one of the blocks is floating. So, it's not your standard terrain):


Deleted blocks (The white blocks are the places that were deletes. It does indeed dig down but white is just an indication of a changed area):


Updates to come:

-Saving/Loading the map based on what was changed. A complete voxel editable world.

-Smoothing out the cubes so it has a more appealing look instead of a Minecraft look.