Love it or hate it, Call of Duty undeniably changed the FPS genre. Things were completely different prior to the first game’s 2003 debut, and, were it not for this oft-debated military shooter franchise, first-person shooters may not have enjoyed the explosion in popularity they experienced in the late 2000s.

Sure, the series has done a lot of bad in recent years, with the normalization of loot boxes and microtransactions a chief concern among avid gamers. Yet, we owe quite a bit to Treyarch, Infinity Ward, and Activision, as some of the advancements we now take for granted wouldn’t exist were it not for their efforts.

10 Normalized FPS Controls

Prior to Call of Duty’s ascendance into the limelight, controllers and FPS games just didn’t go together. Ports of popular twitch shooters like Doom or Quake were often seen as vastly inferior to their PC counterparts, and many early 3D shooter attempts like the first Medal of Honor or the extremely famous 007 Goldeneye were clunky and beyond awkward.

Call of Duty normalized control schemes and set the groundwork for how things should be handled in the future. FPS controls are more or less standard across the board these days, but, were it not for CoD, that probably wouldn’t be the case.

9 Made Multiplayer A Must

Sure, multiplayer shooters were popular long before Call of Duty hit the scene, but fan-favorite competitive FPS titles were usually PC-exclusive prior to 2003. It may not have been the very first game to draw players to Xbox Live or the PlayStation Network, but, starting with Call of Duty 2, multiplayer was an absolute must.

For years, games that had no business including a multiplayer mode had one shoehorned in. In fact, Call of Duty’s multiplayer was so influential that, for the first time, multiplayer-only FPS titles became viable on console. Heck, multiplayer became such a big deal that Black Ops 4 threw out its single-player campaign entirely.

8 Lowered The Barrier For Entry

We don’t intend to patronize Call of Duty fans, but there’s no denying that the barrier for entry has been significantly lowered since the days of frantic, high-skill shooters like Unreal Tournament or the original Counter-Strike.

Popularizing things like auto-aim, killstreaks, and heavily customizable loadouts, Call of Duty lowered the bar and allowed just about anyone to join the fray. It’s one of the most divisive aspects of the series, as some hardened FPS veterans hate the random elements of CoD’s multiplayer offerings. Still, it undeniably contributed to the popularity of the games, and it’s what allowed Call of Duty to stand out against some more demanding multiplayer titles.

7 Defined the Military Shooter Genre

Id’s Wolfenstein 3D was the first shooter to earn mass appeal, and, though it was neither an original IP nor a truly three-dimensional title, it set a precedent for insane action and strange fantasy elements which would be further iterated upon by the likes of Doom and Quake.

Years later, Call of Duty would do the same thing for the Military FPS subgenre. Fantasy was out, and realistic campaigns and recreations of historic battles were suddenly in vogue. Once again, though games like Medal of Honor started this trend, the original Call of Duty and its sequel kicked it into high gear.

6 Brought Controversy Back To Gaming

The early 90s were rife with controversy as lawmakers scrambled to regulate and control potentially affecting titles like Mortal Kombat, Doom, and the ever-offensive Night Trap. Yet, ten years later, much of that had died down, perhaps as a result of much much more pressing real-world events.

However, Call of Duty brought some of that controversy back to gaming—the FPS genre, in particular—in 2009 thanks to the depiction of an airport massacre in Modern Warfare 2. The player’s potential involvement in the atrocity made the sequence all the more questionable, and it once again turned the public eye toward a subsection of gaming which hadn’t been widely-publicized since the Wolfenstein 3D days.

5 De-Emphasized The Campaign

It may seem counter-intuitive given what we’ve already said regarding the series’ legendary campaign elements, but Call of Duty—its modern iterations, in particular—de-emphasized story elements so much that many shooters dropped them altogether.

As previously mentioned, Black Ops 4 replaced the traditional campaign with a controversial battle royale mode, and titles like the original Titanfalland Rainbow Six: Siege didn’t bother, either. Though 2019’s Modern Warfare may have re-aligned the series’ output with fan expectations, for quite a while, FPS campaigns felt like four-to-five-hour, tacked-on garbage only there to fill a quota or appease old-school fans.

4 Moved The Genre Away From WWII

The very same series which made the second World War the go-to conflict for military shooters subsequently totally abandoned it shortly after. 2007’s Modern Warfare was a breath of fresh air for an industry which had been treading water for nearly half a decade, and, after that, realistic combat set against vaguely Middle Eastern backdrops were all the rage.

That would later give way to more sci-fi elements, and some shooters would even follow Call of Duty to space and back. While the franchise eventually returned to WWII with its bluntly-titled 2017 entry, that would only serve to reaffirm how thoroughly that era of FPS gaming had been killed off.

3 Normalized Loot Boxes and Microtransactions

Though it was far from the first video game franchise to introduce annoying, potentially predatory monetization schemes, Call of Duty was quick to normalize these practices within the FPS space. Beginning with the never-ending tirade of weapon skin packs available for Black Ops II and metastasizing into the full-blown gambling minigames and battle passes seen in recent entries, there’s no denying that CoD had a major hand in making those mechanics as big as they are.

While massive backlash from fans and lawmakers has since helped to curtail this issue a bit, it’s still a major issue for which we have Activision and it’s marquee franchise to thank.

2 Necessitated Brand Recognition

Gamers often complain about the stagnant, repetitive nature of modern FPS releases, and Call of Duty is mostly responsible for that trend. Unaware onlookers would have a tough time distinguishing the first Modern Warfare title from the second or third, but Activision refuses to change because of how popular the Call of Duty name is.

Brand recognition is a huge deal these days, and it’s a major reason why we see so many sequels instead of brand new IPs. Why take a chance on an all-new title when it would be bound to sell were to champion the CoD title?

1 Consolized The Genre

We’ve already mentioned how Call of Duty helped to standardize FPS console controls, but, in a broader sense, the franchise helped to make the genre popular on consoles to begin with. With an overall designed sculpted to be friendly to controllers and underpowered consoles, Call of Duty III—the only console-exclusive title in the franchise’s long history—cemented the series’ place as a console-first experience.

PC ports of Call of Duty are often a poorly-optimized afterthought, and that’s not likely to change anytime soon. Twenty-some years ago, FPS games were few and far between on consoles. Today, it’s one of the pre-eminent gaming genres.

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