If you think that the Nokia Lumia 920 is a tough phone, it is true. Based on these videos, you can see that it has to undergo different magnitude of tests to totally destroy it. Check them out.
This picture above is the face of death for the Nokia Lumia 920. It has survived a beating with hammer, a swing on a piece of wood without issue on the screen (did not crack the screen but the phone died after the bashing by the piece of wood).
And here is the previous tests done.
And if you have missed the initial drop tetst, here is the link.
So, as you can see, it is a pretty tough phone.