REAL ACTION HERO
Kill a criminal in Independence Day from mid-air after escaping
Battlefield Hardline REAL ACTION HERO Achievement / Trophy Guide
Near the end of Mission 9, after you survived the enemy waves you will have to zipline down the building. After a helicopter gets flies into the zipline and pulls you up, you will swing back towards the building.
At this point you have to kill one of the enemies and you only have a few seconds to shoot.
Before you start this, make sure you have a strong weapon like the TEC-9 or the BALD EAGLE equipped. You can switch weapons near the zipline.