Here’s a slightly different take on the Liar Diagonal Slitherlink.
Rules Draw a loop that travels horizontally, vertically or diagonally from point to point. Clue numbers that are not crossed by diagonals are equal to the number of adjacent horizontal and vertical segments used by the loop. Those that are crossed by diagonals are different from that number. Furthermore, in every row and column, there is exactly one diagonal segment, and that diagonal crosses a clue.