Logic Masters Deutschland e.V.

[NOTE : this is a re-upload of a puzzle I published before, but with a wrong clue I copied from an earlier draft (which is ironical for a "liar" puzzle). Sorry to anyone who tried it before! This one should be good.]

A couple days ago, I published with rdrd a first challenging puzzle with liar X-Sums. This one should be on the easier side. It is my first 9x9 chaos construction. I tried my best to keep a good balance between region building and an approachable irregular sudoku resolution. Difficulty should be around 4, or maybe less if you are familiar with chaos construction. Do try the example first, it should be a fun easy intro to the concept. Have fun solving!

Thanks to rdrd for testing!

The puzzle :

Play on Penpa.

Play on sudokupad.

Rules :

- Normal sudoku rules apply

- Chaos construction : Place the digits 1 to 9 once each in every row, column and region. Regions are orthogonally connected and must be located by the solver.

- X-Sums : Clues outside the grid represent the total of the first X digits in that direction, with X being the digit in the first seen cell. The clue also indicates that the first X cells in the row/column from that direction are in the same region, and the next cell (X+1) is in a different region. A "?" is a stand in for any digit 1-9.

- Liar X-Sums clues : For each row/column with clues, two clues are provided. Only one of them (top or bottom, left or right) is fully correct. The other clue is lying and therefore totally or partially wrong.

Example puzzle :

Play on Penpa.

Play on Sudokupad.