Sumico

Where Tetris meets Sudoku. The concept is simple: add and subtract as quickly as you can to obtain a given number. If you need a 5, combine a 3 and a 2 with a plus sign, or a 6 and a 1 with a minus sign between them. Be ready: it’s fast-paced, but you don’t need to be a maths whizz to give it a blast.