This is the 2nd wall built following a Rocksolver design. The sequence below shows the virtual wall being subject to the same simulated earthquake as demolished the first wall.
This wall is a little more stable although it does exhibit a classic circular slip line (the red line) which is where the wall eventually fails. In geotechnical terms this is called rotational failure and is a common cause of landslides (for example see the British Geological Survey http://www.bgs.ac.uk/science/landUseAndDevelopment/landslides/How_does_BGS_classify_landslides.html).
We can prevent this sort of weakness by programming specific stability criteria into the Rocksolver software. I should also point out that the friction between blocks in the virtual world is much less than for real-world rocks. So if it stands up in the virtual world then there’s a good chance it’s gong to be stable in the real world.