Armor Piercing (Special Ops)

Armor Piercing is the third mission in the Echo set of Spec Ops mode, and is the 23rd and Final mission of the mode. 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. 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 infront - 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.

Run and Gun
One of the more obvious and more difficult tactics, it is possible to take the machine guns given to you at the start of the level and simply charge through the Juggernauts, aiming for their heads and unleashing the exceedingly large magazine into their faces, however come Veteran difficulty, this option is much more difficult.

Hide and Snipe
By far the most effective tactic, hiding and sniping allows you to stay clear of the Juggernauts bullet spray and pound their heads with large caliber bullets. One particularly good spot to do this method is quite early on in the level, at the top of a ladder near an ammo crate. An SVD can be found up here.

Once you start, head over to the weapons carpet and trade your Thumpers for the Thermal Intervention and Barret .50cal (there's only one of each, and it honestly doesn't matter who gets what) whilst keeping your LMG's. Head up the steps and sprint through the first room and up the flights up steps to the outside of the rig again. Chances are there'll be a Juggernaut around here, so you could either wait for him to come down, or spot him and then turn tail and run before he kills you. Either way, you're gonna need to snipe his brains out or mow him down with LMG fire. If he doesn't appear, just follow the instructions below, because trust me, he'll be showing up soon enough.

Having slain the first of many to come (or not), head outside and turn right. You should see a piece of scaffolding with some planks to stand on and a ladder leading up to it. Get used to this spot, you'll be using it for the next 10 minutes. This amazing piece of mapwork allows you to get a good view of the long section of oil rig the Juggernauts have to pass through, and better yet if they slip past your sniping they have to climb up the ladder to get to you, allowing you to get plenty of hits in before they're able to even start shooting (LMG's to the face are recommended in this situation). Furthermore, underneath the scaffolding is an ammo crate, so should you ever run out, it's there, though as each 'Naut takes about 5-6 sniper shots to the head to kill (even on Veteran), the combined amount of ammo you have in each sniper should already be enough.

From that point, just sit patiently and wait. A Juggernaut should appear every minute or so, so just take them down one at a time. Once multiple 'Nauts start coming, just deal with them in the same way, if all else fails they still have the ladder to climb. An optional tactic is to plant claymores around the bottom of the ladder to warn you of impending danger and to add that little bit of extra damage. Even on Veteran difficulty, this tactic should make this mission as easy as getting a UAV with the Hardline perk on, assuming you can snipe fairly consistently at 'Naut heads.

Note although this method is extremely effective, it is not fool-proof. The biggest problem comes when there are about five Juggernauts left, they often start to come in pairs, and also in quick succession. Since the Barett has quite large recoil you may not be able to snipe both effectively when both are charging towards you. Add to the trouble is that even if you go prone on top of the scaffolding the Juggernauts could occassionally hit you with their LMGs, which although does not kill you outright can stun you enough for you to miss your shot. As there are a few columns close to the right side (from your point of view on the scaffolding) of the scaffolding, if a Juggernaut somehow make it past the "corridor" you are looking down upon towards the backside of the columns there is nothing you can do except to wait for him to climb up the ladder and try to kill him there (which may not always work out). There is also the problem that there is a room (the second breach room in the level The Only Easy Day...Was Yesterday) on the right side (again from your point of view) of the "corridor", and sometimes the Juggernaut would run into this room and completely evades your line of sight. When they run into this room, you again have to run the risk of needing to kill them on top of the scaffolding.

Note that if one of the Juggernauts make it past the column then you would need to wait on the scaffolding for him to climb up. During this time you would more probable than not be facing towards the top of the ladder, and if suddenly there is a second Juggernaut spawning at the end of the "corridor" you would have completely missed him. So when you have killed the first Juggernaut on top of the scaffolding and face back towards the direction of the "corridor" again, the second Juggernaut could silently climb up the ladder and ambush you there.

Given the above possible pitfalls, it is important that you put at least one claymores on the bottom of the ladder as an alarm that a Juggernaut is about to climb up. If that claymore is detonated during one of the Juggernauts' assaults, plant another one whenever it is possible. If you believe a Juggernaut is fast approaching (particularly when there are only a few left, there is a stronger chance that they come in quick succession) and do not feel there is enough time to go off the scaffolding and then climb back up, just put one on top of the ladder.

Also, if you somehow need to deal with two (or more!) Juggernauts on the scaffolding consecutively, there is a chance that you would need to reload your Barett in the middle of the fight. If that should happen, make sure you throw a flashbang right at the Juggernaut to buy you some time.

Video
Video: Solo version of the hide and sniper strategy.

Trivia

 * The description for this mission states that it "probably isn't even possible", yet most players find High Explosive to be much harder.