Residue of a Little Death
This puzzle explores the interaction of modular lines with little killers. It also appears in the Heartburn Collection.
Estimated difficulty: 3.5/5
Rules
Standard sudoku constraints: each row, column, and box must contain a complete set of the digits 1-9.
Standard little killers: Numbers outside the grid indicate the sum of the digits along the indicated diagonal. Digits may repeat along a little killer diagonal if allowed by other rules.
Modular Lines: Every set of three sequential digits along a line must contain a complete set of residues modulo 3, i.e. one digit from {1,4,7}, one from {2,5,8}, and one from {3,6,9}. Digits may repeat on a line if allowed by other rules.
Solve in the SudokuPad app with embedded solution check
Criss Cross
We continue to play with the modular lines constraint in this puzzle, which also appears in the Heartburn Collection.
Estimated difficulty: 4/5
Rules
Standard sudoku constraints: each row, column, and box must contain a complete set of the digits 1-9.
Modular Lines: Every set of three sequential digits along a line must contain a complete set of residues modulo 3, i.e. one digit from {1,4,7}, one from {2,5,8}, and one from {3,6,9}. Digits may repeat on a line if allowed by other rules.
Kropki dots: Digits on either side of a black dot are in a 2:1 ratio. Digits on either side of a white dot are consecutive. Not all dots are shown.
Cages à la Mod
This puzzle was initially started in response to a prompt in a Speed-Setting Contest. We had 77 minutes to set a complete puzzle in which one or more aspects of one or more constraints were not given. Our initial set was broken but this is the cleaned up version. This puzzle also appears in Indigestion Collection 2.
Estimated difficulty: 2.5/5
Rules
Standard sudoku constraints: each row, column, and box must contain a complete set of the digits 1-9.
Standard killer cages: Digits in a cage indicated by a dashed line cannot repeat and must sum to the total shown in the upper left corner of the cage. In this puzzle, not all cage totals are given.
Modular Lines: Every set of three sequential digits along a line must contain a complete set of residues modulo 3, i.e. one digit from {1,4,7}, one from {2,5,8}, and one from {3,6,9}. Digits may repeat on a line if allowed by other rules.
Kropki dots: The digits on either side of a peach dot are in a k:1 ratio, where k is a whole number to be determined by the solver. Different kropki dots may have different values of k.
