Ever since Treyarch introduced their unique Zombies mode in Call of Duty: World at War, the Call of Duty franchise has focused on including a third type of game mode in every entry since. Infinity Ward's attempt at a replayable mode came in the form of Modern Warfare 2's Special Operations mode, more frequently known as Spec Ops.

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Spec Ops focuses on time-trial missions based on campaign levels or unique setpieces. While it would disappear after Modern Warfare 3 and return in Modern Warfare 2019, Spec Ops offers a nice change of pace from fighting infinite waves of the undead. That said, is it a better mode than Treyarch's Zombies? Here are five reasons why Spec Ops is better and five why Treyarch's Zombies mode is still king.

10 Spec Ops: Varied

call of duty modern warfare season 1 spec ops missions

Treyarch's Zombies mode focuses on two things: killing waves of zombies and completing easter eggs. Both of those elements are a major reason why Zombies is so beloved today, yet it can get fatiguing after a while. Spec Ops avoids this problem by having a wide variety of missions that offer unique objectives.

One mission might ask players to escort a VIP to extraction while another might ask players to infiltrate a bank. The older Modern Warfare games excelled at this with a variety of stealth missions, all-out assault levels, and a few vehicle missions to spice things up.

9 Zombies: Weapon Variety

new engine demonstrations image

Since Treyarch's Zombies mode has so few ties with the Black Ops universe, they have few restrictions when it comes to designing weapons. If it wasn't for the unique lore and absurdity of the Zombies universe, fan-favorite weapons like the Wundderwaffe-DG2 and Thundergun wouldn't exist. The ability to Pack-A-Punch weapons multiple times in Black Ops 3 and also gives standard multiplayer weapons some much-needed flair. Black Ops Zombies has a unique weapon sandbox that Spec Ops can't match.

8 Spec Ops: Time Trials

Call of Duty Modern Warfare 2 Spec Ops menu

Opposite of endurance runs is Spec Ops's focus on time trials. Nearly every Spec Ops mission in every Modern Warfare entry will provide players with a higher score if they can complete the mission faster.

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Coordinating with a teammate and optimizing strategies is key to achieving new high scores and three stars in every Spec Ops level. It's the same addictive quality Zombies has but for a completely different reason.

7 Zombies: Simple Gameplay Loop

cod black ops activision

There is no denying that Treyarch's Zombies mode in World at War was a masterstroke in design. Its simple yet intuitive gameplay rhythm of killing hordes of undead compliments Call of Duty's gameplay loop well. It has only gotten better with every installment. The addictive element of pushing for a new record and uncovering new strategies is a major reason why Zombies has survived so long.

6 Spec Ops: Connected To The Campaign

Call of Duty Modern Warfare 3 Snowmobile Spec Ops level.

Call of Duty campaigns are mostly ignored by players, which is a shame considering how good some of them are. Instead of making an entirely new universe for Spec Ops, Infinity Ward instead places Spec Ops missions in the same world the Modern Warfare campaigns take place in. Not only does this help with cohesion, but it gives the developers unique opportunities to expand the main campaign.

Modern Warfare 2's Spec Ops missions let players enjoy campaign level segments with new weapons or objectives. Modern Warfare 3 went as far as to create Spec Ops missions that show the enemy's perspective on a campaign level. Even the rebooted Modern Warfare uses the campaign as a springboard for exploring the conflict between the Coalition and Allegiance that plays straight into the game's various seasons. It makes these missions even more memorable while expanding the Modern Warfare universe in a non-convoluted fashion—which is something the Zombies universe is less successful at.

5 Zombies: Maps

Call of Duty Black Ops 3 Origins Remastered

Similar to Modern Warfare's Spec Ops mode, some of Treyarch's Zombies maps in World at War and Black Ops were based on multiplayer maps—Verruckt is based on World at War's Asylum, and Black Ops's Ascension is loosely based on the Launch multiplayer map.

Of course, this is no longer the case. Ever since the second DLC for Black Ops, every Zombies map has a unique layout that was built specifically for the game mode. As a result, every map has gotten more and more ambitious and better executed. Maps such as Origins and Mob of the Dead are regarded as some of the best Zombie maps of all time for good reason. Spec Ops has nothing remotely similar to the sheer scale and depth of these maps.

4 Spec Ops: Survival

MW3 Survival Mode gameplay

Modern Warfare 3 introduced Survival mode to Spec Ops to compete with Treyarch's Zombies mode. Similar to Zombies, players must survive against waves of gunmen to purchase better equipment. Instead of unlocking rooms and completing an easter egg, players purchase new guns, perks, AI squad members, and even killstreaks to stay alive.

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MW3's enemy roster was also quite varied, including helicopters, explosive attack dogs, and chemical soldiers. Infinity Ward's take on the mode in Modern Warfare is not as interesting due to the worse enemy variety and removal of squad members. Still, Survival mode in MW3 and Modern Warfare offers a great twist on the wave-based survival modes Zombies started for the franchise.

3 Zombies: Easter Eggs

Call of Duty Black Ops Moon map

Easter eggs in Zombies morphed from small secrets to fully-fledged mission objectives. These objectives are rather obscure, though, so players will need to work together to complete each map's main easter egg. Some of these objectives are so complicated that the entire Zombies community will collaborate in the first few days of a new map release to get it solved.

As a result, these easter eggs transcend typical mission objectives or silly developer secrets. The reward for completing these easter eggs can vary from obtaining every perk in a map to beating the level itself. When these easter eggs also tie into unique boss fights and cutscenes, it's easy to see why some members of the community adore Zombies for its easter eggs alone.

2 Spec Ops: Emphasis On Co-op

Call of Duty Modern Warfare Spec Ops Juggernaut and tank.

Despite Zombies allowing for four-player co-op, the mode rarely encourages players to work together besides completing easter egg objectives. Spec Ops is the polar opposite. Completing these missions solo is possible but much more difficult when compared to bringing a friend or three.

Most Spec Ops missions in Modern Warfare 2 and 3 were designed around two players, going as far as to put the second player in a different role entirely. The rebooted Modern Warfare might not go to this extreme with its levels, although its implementation of character classes encourages players to coordinate their loadouts.

1 Zombies: Replayability

Call of Duty Black Ops 2 Mob of the Dead

No third game type in the Call of Duty franchise has the same replay value as Treyarch's Zombies mode. The game mode is incredibly easy to get into but hard to master. Players spend hundreds of hours pushing for high scores by developing new strategies and mastering Call of Duty's movement and gunplay.

Zombies offers a unique style of gameplay that has not been successfully replicated in any other Call of Duty not made by Treyarch. Whether it was Ghost's Extinction mode or Advanced Warfare's Zombies, none hold a candle to the round-chasing Zombies mode Treyarch founded. When that addictive gameplay loop is supplemented with easter eggs and progression systems, it's clear why Zombies has become a core part of Call of Duty's DNA.

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