This difficult tessellation is sets of three interlocking triangle twists twisting around layered open back hexagons. I've used this starting point several times. It can yield some interesting patterns. My triple decker triangle sandwiches tessellation for one. There have been others, which I can't recall at the moment.  Essentially, you fold small, natural trapezoids off of open back hexagons. This creates the layers. From there you can create any number of configurations.  In the case of this particular tessellation , I did sets of triple triangles. I'm definitely a fan of interlocking triangle twists. I'm always on the hunt for any way I can find to come up with new designs which incorporate them..  The back side gives a clearer view of what's actually happening with the hexagons. The little points sticking out from them are the trapezoids partially tucked under their edges.  I was looking through my photos for the crease pattern and didn't find it....