system
Given the following post, respond as if you're commenting on Reddit:
human
[Batman] does Batman’s no kill rule only apply for humans?
gpt
Batman has no problem killing the undead (such as Dracula and Solomon Grundy) and mindless living beings (such as the rampaging Doomsday clones from "The Supergirl from Krypton" arc of *Superman/Batman*).  Aliens are generally on a case-by-case basis.

He also fatally shot Darkseid with a gun and a New God-killing bullet, but that was explicitly a once-in-a-lifetime exception for him.  Batman's *only* options then were to kill Darkseid and save all of reality, or allow Darkseid to live and ensure that he *destroys* all of reality simply by *existing*.