So I'm working on a scene, where I want an NPC to attack a bandit that's creeping up on the player, and then decapitate the bandit and then have another NPC comment on it.

So, because I've got some very specific dialogue in mind, I'd like to actually have the first NPC always decapitate the enemy bandit.

But I'm a little unsure on how I'd go about doing this. Any ideas?

I hate to bump things, but I'd really like an answer to this, and I'm on what, the 6th page now?

Hmm take a look at the perk that gives the decapitate chance. Duplicate it and manipulate the chance to be 100%. Give the NPC in Question that new perk. That's how I'd approach it. I've tested nothing of this, but it should be worth a shot.

Edit: Maybe have a look at the dunTargeOfTheBlooded Item Perk and Effect and do something similar so the perk effect is only applied when the new weapon is equipped, that might save you the hassle to write a script that adds the perk to that character.

Can NPCs even use perks? I know in Fallout 3 and New Vegas NPCs couldn't use perks (and the perks seem to be treated by the engine exactly the same).

in the npc edit window click on the spell list tab, there is a box for adding perks