I made 3D sudoku, books on paper called SUDOCUBE, with a coded index for the clues, using Opus 4.7 I think it was, which came up with the algorithm and extended my own pre-LLM Kakuro codebase:
A couple years ago I wrote a rough CLI based proof-of-concept of a different form of 3D Sudoku. Funny enough, just this morning I was thinking about using Claude to turn it into something actually playable.
Have you seen ColorDoku or MeowDoku? Much better for me to fill colors than numbers. Colors would fit perfectly in a 3D cube, just an idea