It's not enough to kill the villain. You need to have the villain confess to their crimes first. At least for some righteous avenger character types.

Imagine playing a character of this sort who insists on doing this not just for the Big Bad, but also for all their henchmen, lackeys, guards, servants, and also the hordes of orcs and goblins who inhabit the dungeons around the main lair.

"No, don't kill him! Let me talk to him! You! Goblin! Were you part of that raid on the village last week?!"

Transcript

Luke: Well, there's always my hands. I climb up.
{Vader appears}
[SFX]: whooom!!
Luke: Obi-Wan told me about your crimes. You destroyed the Jedi. Admit it!
[SFX]: kzzrzzkk!
[SFX]: whooom!!
Luke: I'm going to hear you confess before you die.
Luke: You killed Obi-Wan!
Luke: You killed your own mother!
Luke: You killed Padmé!
[SFX]: whooom!!
[SFX]: whooom!!
[SFX]: whooom!!
Luke: Say it now and we can make this quick!
[SFX]: whooom!!
Darth Vader: I care not one jot for your sanctimonious misconceptions. You who killed my son.
Luke: Yeah, about that...
[SFX]: whooom!!
{Vader slices Luke's hand off}
[SFX]: Sliiiiice!
{beat, Luke aghast}
R2-D2: You know, I think we've actually run out of hand jokes.