Mark Sweep's puzzles

If you're here just for the practice puzzles, scroll all the way down to the bottom of this post. This post is also quite late after the WSPC, but I just did not have the time and motivation to finish up this post earlier. This was my third time participating at the world championships, being part of the Dutch B-team for Sudoku and the Dutch A-team for Puzzles. In general, I immensely enjoyed this event. It was very well organized, went smoothly, and most puzzles were of very high quality! So huge credits to the organization and author teams for making this happen.  WSC 2025 Individual ranking: 82nd/252 Team ranking: 17th/63  It was a nice surprise to me that I placed top 100 in Sudoku, considering I had not solved many prior to this championship (as all my practice goes into WPC). I did love the variation between rounds, with several rounds feeling quite different from regular Sudoku. For me that's perfect, as the weirder or more puzzle-like it gets, the better I tend to be a...

This should be a relatively easy hybrid. The clues are rather restrictive with this particular ruleset, especially from a setter's perspective, so I might try setting another with slightly modified rules in the future. Rules Shade some cells to form a non-intersecting loop which does not touch itself, not even diagonally. In addition, place lights in some unshaded cells so that every unshaded cell is illuminated. Lights illuminate the cell they’re in as well as all cells seen in a straight line horizontally or vertically, not obstructed by a black cell (either a clue or the loop). Lights may not illuminate each other. Clues cannot be shaded, and represent the number of shaded cells in the (up to) eight cells surrounding the clue, as well as the number of lights in the (up to) four cells surrounding the clue (e.g. a clue of 1 means there is 1 shaded cell of the loop in the eight surrounding cells and 1 light orthogonally adjacent to the clue). Solve online