Double Kill

From Halopedia, the Halo wiki

Doublekill Medal.gif

The Double Kill Medal is awarded for killing 2 opponents within 4 seconds of each other. It is available in all Multiplayer gametypes and has a Bungie difficulty rating of 5 (out of 10). It is represented by a brass medal with 2 stars. When someone gets this medal the announcer will shout "Double Kill!" to the player that recieved this medal.