True to its nature, Armor Piercing pits you against 15 enemy Juggernauts, which is an enormous challenge to overcome should you not be prepared with the proper strategy. Taking place on the oil rig from the mission 'The Only Easy Day...Was Yesterday', a typical playthrough would involve the players slowly reaching the top of the rig, taking down the Juggernauts that confront them along the way. An Ammunition Crate can be found on the second floor of the oil rig. If the player chooses to wait at a specific point on the map, the Juggernauts will slowly come to anyway, leaving you no easy way out of the situation. Thankfully, most of them come one at a time, but the final few come in two's and even three at once.
If the players proceed far toward the top of the oil rig, there is a possibility that Juggernauts may spawn behind them rather than in front - it is important to bear this in mind, and using the Claymores given at the start of the level as a warning system is usually a good tactic.