This takes place on Episode 9 - Independence Day, when the objective is to "Get to the Boat". Before going to the balcony, use the armoury to equip a Bald Eagle with Optics and a Heavy barrel, as this is the best weapon combination to use for the achievement. As you reach the balcony, a cutscene will begin where you begin to zipline and are hit by a helicopter. As you change direction, your character will pull out his pistol and you must kill an enemy before hitting the balcony, which is about a 2-3 second window of opportunity. Aim down the zipline, slightly to the right, and shoot at the flashlight. Pause your game just as you are about to hit the balcony! If you got the kill, the achievement/trophy will unlock, and if you didn't select "Restart Checkpoint". If you wait too long, the game will not allow you to restart the checkpoint. Keep trying until you kill someone!