Skip the grind: Call of Duty: Modern Warfare 3 Zombies lets you unlock any multiplayer gun in minutes

pcgamer.com:

For all the ways that Call of Duty: Modern Warfare 3 feels like an add-on for last year's game, it deserves some credit for shaking up the standard 1-55 progression system in a major way. Instead of unlocking every gun, throwable, and gadget just by leveling up, a huge chunk of MW3 items are locked behind new Armory Challenges.

Nearly half of MW3's guns are unlocked this way, and the only way to complete armory Challenges is to finish your three Daily Challenges. That's right, a challenge to complete challenges. You only get three Daily Challenges per day, but you can continue to grind Armory Challenge points by winning matches. It's a little confusing, especially for CoD fans who've been unlocking arsenals the same way for 20 years, but the new system has its upsides. You can now unlock a lot of the arsenal in whatever order you want—it just might take a little longer to get everything. That is, unless you tab over to Zombies mode. 

Modern Warfare Zombies, it turns out, offers an alternative method for unlocking darn near every gun and throwable in the game. MWZ being built off Modern Warfare 2's DMZ mode means it shares one very generous rule: Whatever guns or grenades you can extract from the map are permanently unlocked in multiplayer.

Guns can be acquired a few ways in MWZ. The easiest is to simply extract out of a match with one of the contraband weapons the game supplies by default, but the more common ways are to buy them from marked areas on the map or find them as rewards for completing contracts. Once you have what you're looking for, all you have to do is make it off the map alive. The first gun I'll be trying this out with is the FR 5.56, MW3's version of the FAMAS that's locked behind the Armory.

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