Jishaku (the name is Japanese for “magnet”) starts out simply – just place a magnetic hematite stone on the dimpled foam game board without dislodging the rest. But the more stones you place on the board, the trickier it gets as the magnets repel and attract in surprising ways. One wrong move and you’ll get “stoned” – as the magnets’ attraction pulls them clicking and clattering into a clump of defeat.