9 Times Batman Broke His One Rule And Killed

2. Shot Darkseid (Final Crisis)

Final Crisis sees Darkseid's spirit falling to Earth, setting in to motion the sundering of reality itself, creating a singularity at the heart of creation, into which all of space and time are slowly being drawn, setting the stage for the evil god's final victory.

In Final Crisis #6, he is confronted by a number of heroes who are trying to save reality itself. After having killed his son with a bullet made of Radion - a substance that is toxic to the New Gods - Darkseid finds himself facing down the barrel of a gun wielded by Batman with that very same bullet in it. Batman fired the gun and intended to kill the villain, even stating explicitly that he'd break his one rule to do so, given the dire circumstances the universe was facing, and was killed by the Omega Beams that Darkseid fired off simultaneously.

The shot hit Darkseid in the shoulder and wounded him terribly, but it didn't kill him - although the fact that he would probably have died from the wound anyway, the fact that he was finished off by a group of other heroes soon after, and the fact that Batman was explicitly trying to kill him means it has to be included on this list.