Locating a Mercenary Convoy in Modern Warfare 3's new zombies mode is a bit of a trial. While completing story missions for the mode, you'll be tasked to find and wreck one of these motorcades as part of the Interceptor mission, but there's no real info about their location. Even though destroying a convoy counts as a little event in its own right, they won't appear on the map unless you get close.
If you're still coming to terms with zombies, our MWZ tips might help you overcome the Exclusion Zone. Otherwise, here's how to find a Mercenary Convoy in Modern Warfare 3 zombies for the mission, and get a Mercenary Stronghold Keycard while you're at it.
Modern Warfare 3 Mercenary Convoy location
The best place to find Mercenary Convoys in MWZ is on the big two-lane highway that circles the entire map, passing along the border between the low threat zone and the orange medium threat zone. Each convoy consists of three pickup trucks filled with mercs, so you'll want to bring a sniper rifle, or something you can use to pick them off. The good news is that shooting the convoy will immediately stop it and make the soldiers disembark, so you won't have to block the road or use a launcher.
When you load into zombies, grab a vehicle and drive along that main highway. Once close to a convoy, three red vehicles will appear on the map, and you'll often get a little radio dialogue mentioning there's one nearby. I've had the most luck finding them in both the north and the south, where the highway passes above a large city area. Even though their appearance is random, there is more than one convoy, so if you keep searching along the highway, you'll find one nearby before long.
To actually complete this random event you need to kill all of the mercenaries—doing that will count towards finishing the Interceptor mission. Make sure to loot the Mercenary Caches on the back of each truck and search around the bodies to grab your Mercenary Stronghold Keycard—just like keycards in DMZ, this is a little blue glowing square. Taking down these convoys is the best way to get these keycards.
They're especially valuable because they allow you to raid a Mercenary Stronghold and grab the Legacy Stronghold Keycard, which can be used to assault the main merc base in the north of the map and open the boss's hideout there to fight him for a special reward. Word to the wise, though; make sure you're equipped to take down an attack helicopter before you try this,
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