Semi-symmetric Vanilla 2 and 2HThis is a plain vanilla Sudoku however the solution is semi-symmetrical. There are four unknown number pairs and an odd number (which of course goes in r5c5).
Each number pair is semi-symmetrical, consider for example that the number pair is 4,7, so if r3c1 contains a 7 then r7c9 must contain a 4 or a 7.
Semi-symmetric Vanilla 2No fishes are needed.Semi-symmetric Vanilla 2HSome fishes are required.Code:
8.......2.4...617..........4...27.9......4..7.8.....1....3....1..1..83.5......7..