Paper Beats Rock

Paper Beats Rock is an achievement for Halo: Reach multiplayer matchmaking added to the Defiant Map Pack with the release of Halo: Combat Evolved Anniversary. The achievement is earned by assassinating a player that just exited Armor Lock in a matchmade game. It can only be unlocked on a Defiant map.

Trivia
The achievement's name is a reference to the game Rock-paper-scissors.