Teaser

Teaser is a puzzle game in a 3x3 grid of bits. Each bit can be either 1 or 0. The rules are simple. The player can change a 1 to a 0, but not the other way around. When changing a 1 into a 0, it also influences its neighbours. When performing the change in a corner, each adjacent number (including diagonally) switches state. When doing the change in one of the four edge positions, the entire edge changes state. Lastly, when doing the change in the centre all adjacent (excluding diagonally) change state. The goal is to get all ones, except for the centre.