Back to school, when I doodled my checkered notebook sheets.
I remember I began with a 4x4 square, then turned in two pentagons... Added horn on each copy...
'Till this little dragon accidentally appeared.
After that, some of them regularly popped in margins of many other notebooks.
At this time, I didn't know who was M.C. Escher. You can imagine the slap it was for me when I discovered his work few years later.