Conway's game of life simulation is happening, but additionally, there is an invisible 3 cell by 3 cell square Angel that is slowly moving across the board in a steady direction.

every step of the simulation, the Angel toggles the alive/dead state of the cells she covers, acting as an external influence on the regular Conway's life simulation.

find this Angel by noticing the abnormalities in the simulation, and click on her. it will let you know when you find her.