Yes, the Riddle of the Sphinx continues to present itself with fresh challenges each time I encounter it. You mentioned:
“Riddles bring back the Mystery to life … of life”
I like your use of capitalization here, equating Mystery with other grounds of being such as God that also get capitalized. I think it’s especially true that riddles bring back the Mystery, suggesting a resurrection, a return — certainly something Campbell posited in so many contexts. The ongoing bringing back of the Mystery is a rhythm of wonder that we can continue to engage in and observe with awe. Occasionally we have a part to play ourselves in the bringing back of the Mystery. And those, those are the moments.