Logic Masters Deutschland e.V.

At the same time as the skyscraper one, ChinStrap came up with this concept for a doppelgänger puzzle, I hope you like the take on it.

• Doppelgänger Sudoku:
  • In the 9x9 grid, every row, column, and box contains a 0 always, as well as eight out of the nine digits from 1 to 9 (ie, it's missing one digit)
  • No two rows, no two columns, and no two boxes may be missing the same digit
  • For each 0 in the grid, the digits missing in its row, its column, and its box must be three different digits.
  • Fill the cells outside the 9x9 grid with the digit missing from the corresponding row, column or box.
• Modified numbered rooms: Spaces around the grid contain the same digit as the digit placed in Nth position looking into the grid in the row/column, where N is the digit missing in the row/column.
• Digits in a big circle must appear in the surrounding four cells at least as many times as they appear in the circle.

Online in Sudokupad (and with extra note space).

See also:

• alte karte / ferneiland
• the cost of giving up
• the year of the dög
• huisgenoot gezocht (ft. ChinStrap)
• don't hurt yourself (ft. Calvinball)
• got too many pages stuck together + zuul with ThePedallingPianist
• split pearsonality / dopealgänger