The Last Light / make one
Your starting
lights.
Make an arrangement. Try to turn it all off. Pass the starting lights on.
Pressing a square flips it and its immediate neighbours above, below, left and right. The cross stops at the edge.
01 / cross-construction
Make starting lights
Begin dark. Each press changes a whole cross, even when all lights are off.
0 on16 off
This blank design is already off. Press a square to make a starting board.
Start with the dark board. Press a square to change a cross.