Firing Squad was the puzzle where I discovered the sliding multipush block crash I brought to your attention on the Steam forums. I was trying out different stuff for the final push and suddenly the game crashed... then it crashed again at the same moment, and I realized it wasn't just a one-off. Aside from that, it was a super-fun puzzle! I picked up on the idea of setting up the sliding eye firing almost right away, but actually figuring out a way to set it up that worked was another story altogether. Ah, an explanation for why it happened! Infinite pushes at the center of the explosion., huh?