For a game that’s still technically in beta, Call of Duty’s DMZ sure has been one hell of a fun experience. DMZ’s latest twist concerns a new playable area selectable when loading into DMZ — but you’ll need a keycard to get in. You can find keycards for this new area throughout Al Mazrah. So, want one? Worry not: This guide will cover a few common ways you can find Building 21 keys as well as how to stay alive long enough to successfully escape with one.
Missions to Building 21 are greenlit for those with access cards in the DMZ. Engage with extreme caution in this research facility, as competing Operators and high-tier enemies will be weapons free. Successful exfil is critical.
— Infinity Ward (@InfinityWard) December 19, 2022
DMZ is a PvPvE extraction-based game mode that’s new to Warzone 2.0. Here, multiple squads of three deploy into CoD’s battle royale map, Al Mazrah, compete for lootable resources, square off in intense gunfights with blisteringly difficult (sometimes unfairly so) bots, and other players who may or may not be your friends. Get in, do what you set out to do, survive, exfil, rinse and repeat. Until now, Al Mazrah has been the only map available in DMZ. That sort of began to 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 too.
Where to look for Building 21 Keycards
Like other gear in DMZ, Building 21 keycards are randomly distributed. But you can prioritise 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 up on discoveries in this mode (and will likely be one of the first places players will start reporting the discovery of an entry point to Building 21). As a note: You can only store 20 keycards in your stash at any given time. So if you’ve been stocking other keys for random locations, you might need to use those up before aiming to find a Building 21 keycard. There seem to be three kinds of Building 21 keycards, the “Blue Access Card,” the “Red Access Card,” and one called “DRC Building 21 Access.” These seem to come in “used” and “worn” varieties, though the meaning of that isn’t known right now. Based on how other keys work in DMZ, it’s safe to assume this indicates how many uses you’ll get out of a key.
Players are also discovering notes with ultra-cryptic hints about Building 21’s location. No one’s been able to make heads or tails of these yet.
Red and orange loot caches, though rare, seem to be a good source of keycards. The chance of one containing a keycard is entirely up to RNG, however. You can find these caches, usually, in Strongholds, Fortresses, and on the train that moves around the map. These are dangerous locations, so be on your guard. If you get lucky and find one on first try and without much of a firefight, it’s time to get the hell out of Dodge to stash that key in your inventory.
Random supply drops can contain keycards, too. These spawn randomly (you’ll hear an announcement that a supply drop is on its way — as will every other player you’re competing against). But you can also trigger one by capturing a SAM site.
Speaking of which, if you have the faction mission asking you to capture a SAM site and loot a supply cache it shoots down, you can possibly kill two pigs with one stone here. DMZ is often about finding opportunities to take out multiple objectives at once.
Supply caches shot down by SAM launchers can contain Building 21 keycards.. Unlike loot caches and other supply drops, capturing a SAM site and causing a supply cache to fall from a plane is something you have a bit more agency over. It’s not a bad agenda to set when loading into the DMZ.
The commander’s helicopter seems to have Building 21 keycards. As all DMZ players know, at random times and locations, a very lethal and aggressive helicopter will spawn in, loudly announcing that you need to leave the area and that it will fire on anyone it spots (god help you if it does). If it’s within a captured SAM launcher’s range, or if you have the right equipment, you can take it down and loot the remains. The RAPP H is a great LMG for this — and you can load it up with anti-armour munitions if you have that on hand (you can select it as a part of your Field Upgrade when loading in). Bots also commonly carry around rocket-propelled grenades, particularly bots which patrol small villages.
DMZ: How To Stay Alive While Hunting Building 21 Keycards
DMZ is unpredictable. Setting out with a specific agenda in mind is smart, but you can never tell what the random combination of loot, bots, and players will bring. Here are some general tips if you’re heading out in search of keycards for Building 21.
When loading into DMZ, pick whatever weapons you’re comfortable with but make sure you or your team has some combination of the following:
Tactical Equipment: Spotter Scope or Heartbeat Sensor
Lethal Equipment: Proximity Mine or Claymore
Field Upgrade: Recon Drone, Munitions Box, Portable Radar, or Anti-Armour Munitions Box (if you’re planning to take down the commander’s helicopter)
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’re going in with two friends, you can pretty much cover all these bases or have some room to get experimental.
Because the DMZ is so deadly, you need to prioritise your ability to get to the extraction point if you want to get out with a Building 21 keycard. Toward that end, here are some dos and don’ts:
Do: Approach every location with absolute caution. This is where Spotter Scopes and Heartbeat Sensors come in handy: Maintain a distance from every place that could be remotely occupied and use your Spotter Scope to check an area for opposition. You should never, ever, go into a given area blind in DMZ.
Do: Get the hell out of there the second you find a keycard. Sure, that intel contract looks very tempting. Or maybe you’ve found a safe to crack. Forget it. A Building 21 keycard is what you’re here for, and once you get it, your priority becomes extracting it safely. Getting out of the DMZ is a mission unto itself. Bots might be patrolling the area. Exfil campers (re: other players) might be scoping the area. Approach with caution. Send one person in to call in the chopper; retreat to safety and race to board it the second it’s within climbable distance. Never let your guard down until you’re safely in the air.
Do: Search every medical kit you see. Since the most recent update, DMZ has more Self-Revive kits and revive pistols. You can find these in a variety of places, but they’re most often in the square medical boxes you find mounted to various walls. Having a self-revive kit can mean the difference between getting out with a keycard and losing all your stuff.
Do: Acquire an armoured vehicle if you can. Sometimes you’ll need to race across the map to hit an extraction point (the 25 minutes DMZ gives you to accomplish all your tasks will evaporate before you know it). Armoured vehicles aren’t invincible and you can take damage from inside, but they fare a hell of a lot better than the game’s other rides.
Don’t: Take on contracts, hack UAV towers, or try to finish objectives other than searching for keycards. You’re here to find a Building 21 keycard. That means you have two objectives: Find a card, and exfiltrate. Although a completed contract is necessary to get an exfil streak and a perk, it might not be worth the risk if you’re just hunting a keycard.
Don’t: Shoot anyone (players or bots) unless shot at. Ammo and armour can run out fast if you’re not careful, and firefights with any opposition in the DMZ can turn into a resonance cascade shitshow of non-stop fighting that will end with your death and the loss of all the loot you’ve gathered.
Don’t: Stay on the train for very long. Yes, that train has great loot (possibly even keycards) but you’re on borrowed time every second spent onboard. It’s a giant beacon for other players to find great equipment, and bots will open fire on it with wall-piercing rounds the second they suspect you’re present.
No one’s totally sure what awaits in Building 21, but having a mystery like this to chase in a remarkably unpredictable mode like DMZ is pretty exciting. Good luck scoring those keycards.