Triple Kill

From Halopedia, the Halo wiki

Summary

Awarded after killing 3 opponents in a row within 4 seconds of each other.

The Triple Kill Medal is awarded for killing 3 opponents within 4 seconds of each other. It is available in all Multiplayer gametypes and has a Bungie difficulty rating of 6 (out of 10). It is represented by a steel medal with 3 stars.