Color WingThe Color Wing technique uses more than one group of conjugate pairs for analysis. In the sudoku diagram below we have two groups (light / dark yellow group, light / dark green group) conjugate pairs for the digit 1. In the fourth column there is one more cell that can have the digit 1 (R8C4), so the cells R2C4 and R5C4 do not form a conjugate pair, but they form a so-called bridge between groups. The bridge is characterized by the fact that one or both cells will not get the given digit. In our case, the dark green R2C4 cell or the dark yellow R5C4 cell or both will not get the digit 1. Therefore, either light yellow cells or light green cells, or both types of cells will have the digit 1. From here we can eliminate the digit 1 from cells that "see" light yellow and light green cells simultaneously, i.e. from cells R1C1 and R4C2. Thanks to this elimination, we can place the digit 8 in the R4C2 cell.
The next example presents two groups of conjugate pairs for the digit 2 connected by more than one bridge, e.g. R7C1 - R7C8 and R4C5 - R4C8. So from all cells that see both light yellow and dark green cells simultaneously, and from celss that see both light yellow and light green cells simultaneously, we can eliminate the digit 2. In addition, we can see that the dark yellow cells forming the bridge are included in the cells for elimination. Therefore, the digit 2 can be eliminated from all dark yellow cells.