This achievement is for killing a ‘Sire’ enemy, whilst it is kidnapping one of your teammates Best Game Mode: Escape (Select the easiest difficulty - Beginner).
1) Select any Hive map (Sires spawn randomly and can be found in every Escape map).
2) Play through the map and keep your eyes open for an enemy hunched over with tentacles flailing from its back. The Sire will run up to you and grab you, allowing the player to release themselves from its grasps by tapping B. You will need to ensure your teammate does not release themselves.
3) Whilst the Sire is latched onto your teammate, you must kill it.
4) Once you have killed the Sire, your achievement will unlock and you can go to the Winchester, have a nice cold pint, and wait for it all to blow over