That's a Knife

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

Trivia

 * The name of this achievement references dialogue from the film Crocodile Dundee. In the movie Mick and Sue are menaced by a trio of punks, one of whom brandishes a switchblade. Sue advises Mick to give the thief his wallet, because the thief has a knife. Mick merely chuckles at the switchblade: "That's not a knife", he scoffs, drawing his much larger outback Bowie knife, "That's a knife.", and slashes the would-be mugger's nylon jacket. When the thieves run away, he dismisses the incident as a prank.