It's week 6 for the Zentangle challenge and the theme this week is to incorporate a new tangle design called Ixorus. This new design is the center area of my Zentangle above. There is a diagram on how to create this design at the link beginning this paragraph.
By the way, if you are new to Zentangles, a great site for learning most, if not all, of the tangle designs is TanglePatterns.com.