You Don't Belong In This World!

 is a challenge added by the Fallout: New Vegas add-on Gun Runners' Arsenal.

Obtaining
To complete this challenge, kill 10 abominations with Katanas, Dynamites, Machetes, Throwing Spears, Throwing Knives, and/or Throwing Hatchets.

Behind the scenes

 * The title of this challenge is a reference to a quote made by Richter Belmont in Castlevania: Symphony of the Night, when confronting Dracula ("Die, Monster! You don't belong in this world!").  Another Gun Runners' Arsenal challenge, The Same Could Be Said of All Religious Weapons, references this conversation as well.