When I teach an introductory Zentangle class, I begin with a few basic tangles that are relatively simple yet lovely to create. What amazes me is how each tile I draw for these intro classes turns out differently, despite using the same set of tangles. In this tile, I like the sweep of the line to the right, accentuated by the shading.
This is a bijou we did together (a smaller 2" x 2" card) to practice Tripoli embellished with circles to connect the triangles. I also added some Tipple to the center part as an experiment.