In my opinion, my greatest triumph was Honeycomb. I don't usually use a ruler for Zentangles, though I had it out for the tangles from this book, and it was obviously indispensable for this design. My daughter looked at it and said, "That doesn't look that hard." Well, let me tell you...it took one false start, and a TINY Micron pen, but I love how it looks:
I am on to the next Zentangle book I borrowed from the library: Let's Tangle! by Kathleen Murray. It is a great introductory book if you are new to Zentangle; I recommend it highly, and will share some of what I have been learning from it in a future post.