That's A Knife is an achievement in Halo: Reach.[1] To unlock this achievement, a player must perform an assassination on an enemy.


  • The easiest way to get this achievement is to play a Forge game with another person, have him stand still, and perform the assassination.
  • You can also play Nightfall, and the first few enemies you encounter are an elite and two sleeping grunts. Any of the Covenant idling there may be eliminated with ease.
  • You could also do this in conjunction with the If They Came to Hear Me Beg achievement.
  • Another easy way to get this achievement is to assassinate one of the sleeping grunts on Corvette.


  • The name of this achievement references dialogue from the film Crocodile Dundee.


  1. Halo: Reach Firefight at Comic Con

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