In an earlier post I created a 4th iteration 160,00 block Menger Cube in minecraft. After I discovered the newly added structure block I was able to construct the 5th iteration 3,200,000 block version.
After I cleared out a large enough area all the way down to bedrock I began construction.
The 32x32x32 limit of the structure block meant that I had to use 3rd iteration 8,000 block menger cubes Menger cubes to construct this because the 4th iteration was more than the 32 cubed or 32,768 limit.
An fun side note is that I constructed this with x = 0, z = 0 at the very center.
With the bottom section of 8, 4th iteration Menger cubes finished I it was time to do the second row of 4,
And the beginning of the top row of 8, 4th iterations menger cubes
From the above picture you can see the outline of the structure block for the 3rd iteration Menger cube. It takes 20 of the 3rd iteration to make a 4th iteration so for each of the 20, 4th iteration cubes I had place the structure block 20 times. That is still a huge drop from having to place each of the 3.2 million cubes.
If you can't make out the y coordinates below this structure goes from y = 0 to just under the minecraft build height limit. What this means is that the 6th generation is not gonna happen in minecraft unless that limit is changed.
Another side note a quick way to clear an area using the structure block is to save a 32x32x32 area of just air then use the structure blocks in the area you need to clear. You could also use the /fill command to fill an area with air but I like the structure block approach.
Here is a few shots of the finished product a megalith of 3.2 million blocks!!!!!!
And here is a few shots of me starting to decorate the inside.