This is a Numberlink puzzle.
It seems I may end up returning to weekly posts after all. You’ll just have to forgive me for the fact that many of them will be rejects from other projects (which are not named Mystery Hunt).
WordPress continues to give ugly thumbnails. Above I’ve employed the best solution I found, which is to upload a manually-scaled thumbnail to show up on the post. Clicking the image will still get you the full-size version. Pain in the butt for me though.