Logic Masters Deutschland e.V.

I was exploring full indexing and wondered how it would play with an irregular grid. Turns out it can be solved uniquely with a few extra Kropki clues, and this puzzle was the result. Note - I didn't use red colouring for column indexing cells, since all the cells in the grid would be red, and testers found that harder to scan.

The Rules:

• Normal irregular Sudoku rules apply.
• Column Indexing: ALL cells in the grid are column indexing cells. For example, all cells in column 1 determine where the 1 goes their respective rows. So, place the 1 in the column number that corresponds to the digit in the cell. For example, if r2c1 is a 5, then r2c5 must be a 1. Cells in all other columns act similarly; for example, if r3c6 is a 4, then r3c4 must be a 6.
• Kropki pairs: digits separated by a black dot have a 1:2 ratio, meaning one is exactly double the other. Not all dots are necessarily given.

  Dotty Reference

  by Chilly

  

  Link for solving on Sudokupad