Sudoku variants: toroidal sudoku

Toroidal sudoku is a particularly hard variety to get the hang of, because the regions go off the page and back on again at the other side.

In other words, it is a little bit like playing pacman where you can scroll off the screen and come back on the other side - you need to take this into account to solve this sort of sudoku puzzle.

It really is a bit of a mind bender!