The grid is made up of magnetic and non-magnetic plates. Each magnetic plate has two halves: one positive (+) and one negative (−). Halves with the same symbol can not be horizontally or vertically adjacent. The numbers outside the grid indicate how many magnetic halves of each kind can be found in that row or column.
The following variants can all be combined.
- With Monopoles: The Diagramm contains also plates of the size of one field. These can't be neutral.
- With incomplete information: Some of the informations at the borders are superfluous.
- Crypto variant: All numbers have been replaced with letter.