Finned Mutant Whale
Uses equal-sized groups of rows, columns, or boxes where one digit appears only across the other group.
All candidates have been entered in the empty cells.
In the 6 groups in A, candidate digit 6 can appear only in the overlaps with the 6 groups in B or at the 4 candidate digits 6 marked C. If any candidate digit 6 marked C is true, candidate digit 6 marked × that shares its row, column, or block is false. If every candidate digit 6 marked C is false, candidate digit 6 in the 6 groups in A is confined to the overlaps with the 6 groups in B. In that case, one candidate digit 6 is true in each group in A. Because two 6s cannot share the same group in B, one candidate digit 6 is also true in each group in B. In this case too, candidate digit 6 marked × in the 6 groups in B is false. In either case, candidate digit 6 marked × can be removed.