Today's genre is Black Belt, an old Omopa from the early 2000s that didn't receive too much attention at the time. I (re?)-discovered this type during a discussion on Discord, when Nick Baxter linked to an old webpage containing pictures of Nikoli magazines. (I dismissed the genre in the Omopa collection, because the given example misses two important rules!)
Rules: Draw a single closed loop of shaded cells, connecting squares horizontally or vertically. The loop may cross itself but otherwise may not touch itself orthogonally (that is, the black cells cannot form a 2x2 block or a T-shape). Clue cells may not be shaded and depict the number of cells vertically or horizontally (up to 4) which are shaded.