Cold Fusion Achievement in Halo: The Master Chief Collection

Fusion Coils are UNSC ground containers that contain superheated plasma. As you would expect, the contents within the container are highly volatile and will kill weakened enemies when the container is destroyed. Lockdown will have many Fusion Coils scattered around the top floor of the middle platform, so start a Custom Game with another player and meet each other here. With a weak weapon, such as the SMG, strip the shields off your opponent and then have them stand next to the Fusion Coil. Now shoot the Fusion Coil with your weapon and the explosion will kill them, thus unlocking the achievement.