Depending on your opinion, can't slaying evils almost be seen as aiding the greater humanity, and to the Maran, it is even counted as aiding the actual evil, so...in a way...depending on your spin, there are viable methods. The only thing that separates, is that if an evil begs mercy, you're supposed to stop, whereas a common Maran viewpoint would be that they are lying and only upon their redemption will the deed be truly done and true mercy allowed, et cetera.