Toroidal Sudoku is essentially Jigsaw Sudoku with jigsaw pieces that wrap around the sides of the puzzle. More generally, it is a traditional Sudoku puzzle whereby the 3-by-3 box regions have been replaced by irregular jigsaw-shaped regions, all of the same size - but these regions are defined as if the puzzle wrapped around upon itself, as if printed on a toroid. In all other respects it works in the same way, but this change in the region shapes introduces new twists into the logic required to solve the puzzle - and it can be pretty tricky to keep track of the regions. Solving the puzzle in colour, as on puzzlemix, certainly makes it easier to keep track of this.
The aim is essentially simple: place the digits 1 to 9 into the puzzle grid so that each digit occurs once in every row, column and bold-lined wrap-around jigsaw-shaped piece.
Some digits might already be given - these constrain the puzzle in such a way that there is only one possible solution, which can always be reached via reasonable logical deduction. Guessing is never required.
We can supply Toroidal Sudoku puzzles (also known as Wrap-around Sudoku) in any size and with a small range of possible variations - from Toroidal Sudoku-X through to more unusual varieties such as Toroidal Skyscraper Sudoku(!).
All of our puzzles are either entirely hand-made or have significant manual input into the process.