Residual Effect

Normal sudoku rules apply. Little killers: Numbers outside the grid give the sum of the digits along the indicated diagonal. Digits can repeat along the little killer diagonal if allowed by the 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 on two-cell lines cannot be from the same residue set. Digits may repeat on a line if allowed by other rules. Unimodular lines: every digit along the line is from the same residue class modulo 3, i.e. all from {1,4,7} or all from {2,5,8} or all from {3,6,9}. EVERY diagonal in the grid, including those marked as little killers, is either modular or unimodular. It is up to the solver to determine the nature of each diagonal. Exported from f-puzzles.com