More on The Division 2
The Dark Zone in The Division 2 should not be taken lightly; you'll be up against elite enemies that control compounds as well as other players that are keen to get their hands on your contaminated loot. You'll also need to defend the chests that allow you to upgrade your weaponry, though you'll need to find the keys that will unlock them.
Dark Zone chests contain some of the best loot available to players—if you're willing to venture into The Division 2's designated PVP zones. The loot you acquire here is also useful in the campaign so it's well worth knowing the best ways to get your hands on those Dark Zone keys.
Elite enemies drop Dark Zone keys in The Division 2
High-level enemies should be your priority if you're looking for Dark Zone keys and they're relatively easy to spot; look for yellow 'named' enemies that lead a pack from the numerous factions in DC. They're often found near the compounds but could also be part of a patrol. Taking them down will give you the chance of looting one of the elusive Dark Zone keys.
You can grab keys from other players, too
The Division 2's Dark Zone has a lot of other players looking to grab loot for themselves and another way to pick up Dark Zone keys is to take out the players that are holding them. While some players might team up and help each other out to gain their share of a pot, most players won't think twice before killing you to nab your hard-earned loot for themselves.
Taking them out first not only nets you any contaminated loot they were holding, but it also gives you any Dark Zone keys they might have obtained. Perhaps this method won't win you any popularity awards but it's certainly a quick way to get those keys. Just watch that you don't get jumped on before you have the chance to use them.
But, you don't need a key to unlock Dark Zone chests
Dark Zone keys can be tricky to find but if you're having trouble getting your hands on one, you can also use a lock pick to open Dark Zone chests—though there is a small catch. Using a lock pick is Rogue behaviour and will make you visible to other players, over time. This really isn't much of a deterrent—the Dark Zone is a PVP zone, after all, so you should be prepared to fight to defend your loot at all times.
This perk makes finding Dark Zone keys easier in The Division 2
You can obtain Dark Zone keys from scavenging loot crates but even this can be made easier by visiting the Dark Zone Officer in your base of operations and unlocking the Dark Zone Perk. You'll need to reach level 25 and you'll then be able to choose the 'Keymaster' perk, a tier six offering that has a 25% chance for the player to obtain a Dark Zone key from loot crates. It may take a while to get to level 25 but it will make scavenging much easier.