Find the mysterious building 21 keycards

You just have to follow the damn train… and not get shot.
gif: Activision / Kotaku

For a game that is technically still in the beta phase, call of Duty‘s DMZ sure was a hell of a fun experience. DMZ’s latest twist involves a new playable area that’s selectable when loading into DMZ – but you’ll need a keycard to get inside. You can find keycards for this new area all over Al Mazrah. So do you want one? Don’t worry: this guide will cover some common ways you can find Building 21 keys, and how to stay alive long enough to successfully escape with one.

DMZ is a PvPvE extraction based game mode that is new Warzone 2.0. Several teams of three are used here cod‘s battle royale map Al Mazrah fight for lootable resources, engage in intense shootouts with extremely difficult (sometimes wrongly) bots and other players who may or may not be your friends. Get in, do what you set out to do, survive, exfiltrate, flush and repeat. Previously, Al Mazrah was the only map available in DMZ. That started Change with Season 01 Reloaded, which introduced a new (and apparently more difficult) area. Many players have already found keycards for the new location. You can also.

A screenshot shows the office-like interior of the new Call of Duty: Building 21 DMZ location.

No it is not control. Behold the new and mysterious DMZ location: Building 21.
picture: activity

Where to look for Building 21 Keycards

Like other equipment in the DMZ, Building 21 Keycards are distributed randomly. However, you can prioritize certain locations to increase your chances of finding one.

For now, much of what follows is based on hearsay and documented examples on the internet. r/DMZ is a great place to keep track of discoveries in this mode (and will likely be one of the first places players will report discovering an entry point to Building 21). Note: You can only keep 20 keycards in your stash at a time. So if you have other random location keys in stock, you might need to use them up before attempting to find a building 21 keycard. There appear to be three types of Building 21 keycards, the “Blue Access Card”, the “Red Access Card” and one called “DRC Building 21 Access”. These appear to come in “used” and “worn” varieties, although the meaning of this is unknown at the moment. Based on how other keys work in the DMZ, it’s safe to assume that this indicates how many times you can use a key.

players are too Discovery of notes containing ultra-cryptic clues to the location of Building 21. So far nobody has been able to make anything out of it.

Red and orange loot caches, while seeming rare, seem to be a good source of keycards. However, the odds of one containing a keycard are entirely up to RNG. You can usually find these caches in strongholds, forts, and on the train that moves around the map. These are dangerous places, so be careful. If you’re lucky and find one on the first try and without much firefighting, it’s time to get out of Dodge and stash that key in your inventory.

Random Supply Drops may also contain Keycards. These appear randomly (you’ll hear an announcement that a supply drop is on the way – as will any other player you’re up against). But you can also trigger one by capturing a SAM site.

Speaking of which, if you have the faction mission that asks you to capture a SAM site and loot a supply cache that she shoots down, you might be able to do it hitting two pigs with one stone Here. DMZ is often about finding ways to achieve multiple goals at the same time.

Supply Caches shot down by SAM Launchers may contain Building 21 Keycards.. Unlike loot caches and other supply drops, you have a bit more leverage in capturing a SAM location and dropping a supply cache from a plane. Loading into the DMZ is not a bad agenda.

The commander’s helicopter appears to have keycards to building 21. As all DMZ players know, at random times and places a very deadly and aggressive helicopter will appear, loudly announcing that you must leave the area and that it will fire on anyone it spots (God help you if he does). If it’s within range of a looted SAM launcher, or if you have the right gear, you can mine it and loot the remains. The RAPP H is a great LMG for that – and you can load it up with anti-tank ammo if you have it on hand (you can select it when loading as part of your field upgrade). Bots also often carry rocket-propelled grenades, especially bots patrolling small villages.

DMZ: How to stay alive while hunting and building 21 keycards

DMZ is unpredictable. Going out with a specific agenda is smart, but you never know what the random combination of loot, bots, and players will bring. Here are some general tips when setting out on your quest for building 21 keycards.

When loading into the DMZ, choose the weapons you are comfortable with, but make sure you or your team have a combination of the following:

Tactical Gear: Spotter scope or heartbeat sensor

Lethal Gear: Proximity Mine or Claymore

Field Upgrade: Recon Drone, Ammo Box, Portable Radar, or Anti-Tank Ammo Box (if you plan to take out the Commander’s Helicopter)

Continue reading: Warzone 2.0‘s DMZ: Everything you need to know about the game’s best new mode

My personal loadout always has a Spotter Scope, Recon Drone, and Claymore, but any combination of the above will work for you. And if you go with two friends you can pretty much cover all of these bases or have some room to experiment.

Because the DMZ is so deadly, you’ll need to prioritize your ability to get to the extraction point if you want to get out with a Building 21 keycard. To that end, here are some dos and don’ts:

Do: Approach any location with absolute caution. That’s where spotter scopes and heartbeat sensors come in: keep your distance from any location that might be remotely occupied and use your spotter scope to check an area for resistance. You should never blindly go into a certain area in DMZ.

Do: Get out of there as soon as you find a key card. Sure, this Intel deal looks very tempting. Or maybe you’ve found a safe to crack. Forget it. A Building 21 Keycard is what you are here for, and once you’ve got it, your priority is to extract it safely. Getting out of the DMZ is a mission in itself. Bots may be patrolling the area. Exile campers (e.g. other players) could scout the area. Proceed carefully. Send a person inside to summon the helicopter; retreat to safety and hurry to climb it once it’s within climbable distance. Never let go of your guard until you are safe in the air.

Do: Search every medical kit you see. Since the last update, DMZ has more Self Revive Kits and Revive Guns. You can find these in a variety of locations, but the most common ones are in the square medical boxes that you’ll find mounted on various walls. A revival kit can mean the difference between getting out with a key card and losing all of your belongings.

Do: Acquire an armored vehicle if you can. Sometimes you have to dash across the map to reach an extraction point (the 25 minutes DMZ gives you to complete all your tasks will fly by before you know it). Armored vehicles aren’t invincible and you can take damage from the inside, but they perform a hell of a lot better than the game’s other rides.

What not to do: Accept contracts, hack UAV towers, or try to accomplish tasks other than finding keycards. You are here to find a key card for building 21. This means you have two goals: find a map and exfiltrate it. While a completed contract is required to get an Exfil Streak and Perk, it might not be worth the risk if all you’re after is a keycard hunt.

Don’t: Don’t shoot anyone (players or bots) unless they’re shooting at you. Ammo and armor can run out quickly if you’re not careful, and firefights with opponents in the DMZ can turn into a resonant cascading shitshow of non-stop combat that will end in your death and the loss of all your loot gathered.

Don’t: Stay on the train too long. Yes, this train has great loot (possibly even key cards), but you’ll have borrowed time for every second you spend on board. It’s a huge beacon for other players to find great gear, and bots will open fire on it with wall-piercing rounds once they suspect you’re present.


No one is quite sure what to expect in Building 21, but pursuing a puzzle like this in a remarkably unpredictable mode like DMZ is quite exciting. Good luck getting those key cards.

Leave a Reply

Your email address will not be published. Required fields are marked *