When it comes to single-player games, players much more likely to experiment with all the weapons available to them. While players may end up picking a favorite, they probably won't put too much thought into how well it performs. Multiplayer games, on the other hand, make this a vital part of the experience. When players unlock a new weapon in Call of Duty, everything from its reload speed to its accuracy is scrutinized heavily, and each weapon's viability soon becomes widespread knowledge in the community. This eventually leads to something called a "meta," when players discover the optimal loadout to use, and it quickly becomes the most common class seen online.

Call of Duty has been around for quite some time now, and over the last two decades or so, the series has seen plenty of metas come and go. While some of these metas only lasted a few weeks before they were patched out by the developers to maintain the game's balance, some lasted a lot longer, and some are even talked about today, living on in infamy.

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The Most Notorious Call of Duty Metas

While online multiplayer had been a part of the Call of Duty franchise since its debut in 2003, it only really gained mainstream attention with the release of Call of Duty 4: Modern Warfare in 2007. With more players than ever, it didn't take long for fans to find and exploit the series' first infamous meta weapon, the M16.

A three-round burst, medium-long range rifle, the M16 has been a staple of the Call of Duty franchise, but it's never been quite as overpowered as it was in its debut appearance. With the Stopping Power Perk equipped, players were capable of killing an opponent in just one burst, and with the M16 boasting some of the highest accuracy of any weapon, players rarely missed. The M16 quickly became Call of Duty 4's most notorious weapon, and it wasn't long before lobbies were filled with the service rifle.

On the World War 2 side of things, Call of Duty: World At War had its own fair share of toxic meta weapons, but by far the most infamous was the MP40. Yet another weapon that's been present throughout Call of Duty's history, the MP40 is always one of the stronger SMGs, but in World At War, it was the most powerful bar none. Though its fire-rate was slower, and its recoil was high, the MP40's damage output was simply unmatched by any of World At War's other weapons, and with attachments, it only became more lethal.

2009's Call of Duty: Modern Warfare 2 had not one, not two, but three infamous metas. The first of these was the UMP45 submachine gun. While the rest of the SMG category has a base damage of 20, the UMP45 has a damage output of 35, putting above even most of the assault rifles in the game. Throw a silencer and Stopping Power on it, and the UMP45 is the best weapon in Modern Warfare 2. However, it isn't the most infamous of MW2's metas.

Akimbo Model 1887s are still brought up in conversations surrounding the state of Call of Duty's multiplayer. Back when Modern Warfare 2 released, players could unlock the Model 1887 shotgun, and attach the Perk Akimbo, which allowed the player to dual wield the weapon. In this form, two Model 1887s ended up having an absurd damage output, and surprisingly, had quite the range. Marking the first time this really happened in a Call of Duty, the akimbo Model 1887s ended up being nerfed. The final Modern Warfare 2 meta, and one which stuck around for subsequent games, is the notorious grenade launcher attachment for assault rifles. Many of Modern Warfare 2's matches would start with the sound of 12 grenade launchers popping off.

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