Perk-A-Colas are some of the most iconic boosters in the Call of Duty world, but which ones should players always be on the lookout for?

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From the many celebrity guest stars to the increasingly difficult maps, the Zombies mode in Call Of Duty remains an all-time classic. Not only do the fans look forward to new maps, but there are still many returning to older games in the franchise to play favorite maps.

In all the Treyarch games starting with World At War, the Zombies mode implemented a way to keep players alive, and perks were introduced in the form of soda bottles. From there, the games would add more Perk-A-Colas with unique abilities, but some perks are more essential to grab than others.

10 Mule Kick

Players are only allowed two weapons when facing the zombie hordes. So a perk that allows a third weapon sounds ideal, right? It is, but this can depend on the situation. It would be the perfect perk for the Call Of Duty campaigns. Having a third weapon can be great, especially when running out of ammunition on the two main weapons.

That being said, if someone with Mule Kick is knocked down, they lose all perks. As such, if that third weapon is fully upgraded with Pack-A-Punch and specialty ammo, that weapon vanishes with the perk upon revival. Mule Kick can be very useful but it requires extra care from the player.

9 Vulture-Aid Elixir

Added in Black Ops II, Vulture-Aid is one of the few Perk-A-Colas to give three abilities. Zombies will now drop extra points and ammo, important items can be seen through walls on the HUD, and with it, certain zombies will emit green gas.

When killed, the green gas zombies will create a cloud that keeps other zombies from attacking the player. While this is a helpful Perk-A-Cola, it lacks longevity since it can only be found in Black Ops II and only on the Buried map.

8 Electric Cherry

It's always so frustrating when the player reloads during a massive zombie horde attack. It exposes the player and some guns reload slower than others. Electric Cherry is the Perk-A-Cola to help with that since it sends out an electric burst to shock any zombies that are too close.

Sadly, the machine for Electric Cherry did not return after Black Ops II. However, with the randomized Der Wunderfizz machine, Electric Cherry can still be acquired through chance in Black Ops III. Electric Cherry would get revamped for Black Ops 4's completely different perk system.

7 Quick Revive

Yes, Quick Revive is arguably one of the most essential perks in zombies. Instead of dying, the player is knocked down for a few seconds and the perk revives them. This perk seems like it should be the best, right? In a way, especially if the player is attempting a run to solve the many difficult Easter Eggs.

Quick Revive only resurrects the player in solo play. In co-op, Quick Revive is only used to revive the other teammate faster if they are downed. However, if one has Quick Revive and is downed in co-op, it does nothing. Even in solo play, Quick Revive can only be used three times before vanishing.

6 Double Tap Root Beer

To be specific, this is referring to the second Double Tap incarnation introduced in Black Ops II and Black Ops III. This root beer increases the fire rate of a weapon by 33% while firing two rounds for the price of one, thus doubling damage.

This improved Double Tap would be so beloved that it was brought onto remasters of classic maps in Black Ops III. There is no drawback to Double Tap II; in fact, it is often depicted as one of the signature Perk-A-Colas for a reason, but since players are often only allowed four perks, they need to make sure it is what they want.

5 Deadshot Daiquiri

Aiming for the head is not that hard in the early rounds, but later on when zombies and bosses are amped up? Precision is often thrown out the window. This is where Deadshot Daiquiri can be a lifesaver since one aim down the sights will instantly aim for a zombie's head, often for an instant kill depending on the weapon.

Now, this one is not 100% necessary to survive but it does help a great amount. Much like Double Tap II, it's a perk that should really be used depending on the preference of the player.

4 Widow's Wine

This perk had the potential to be the best perk in the series but unfortunately, it never lived past Call Of Duty: Black Ops III. Widow's Wine, introduced in Shadows Of Evil, grants the player bombs that act similar to semtex grenades but when they explode, they wrap zombies in webs. Sound great, right?

Well, it gets even better, because they also provide extra defense. If a zombie attacks, the grenades explode on the player and freeze the zombies, allowing them to escape. So if combined with Jugger-Nog, it is essentially another boost of health. On other maps, it can be found in the Wunderfizz machine.

3 Stamin-Up

Nothing is more aggravating than dying just because the character runs out of breath after five seconds of running. Stamin-Up grants a permanent 7% boost in speed and the ability to run for much longer. In some situations, Stamin-Up makes the difference between survival and death.

Stamin-Up was first introduced in World At War and remains another one of the iconic Perk-A-Colas with variants of it in both Black Ops 4 and Black Ops: Cold War. Even Infinite Warfare made its own carbon copy of it known as Racin' Stripes.

2 Juggernog

In Call Of Duty: Zombies, characters do not have much in terms of health. All it really takes is one rogue zombie and it's a death within the first few rounds. To keep the players alive, Treyarch introduced what is often the poster child of the Perk-A-Colas: Juggernog.

Instead of two hits, players can take five hits before dying. That might not seem like much, but those five hits are what keep most players alive for so many rounds, especially when the many boss zombies start to spawn. For most players, Juggernog is the first Perk-A-Cola players should find on a map, hence why it was around from World At War and returned in Cold War.

1 Speed Cola

A common misconception is that Juggernog is the most important. However, Speed Cola is more important for surviving in later rounds. When the zombies get stronger, it is a necessity to upgrade to stronger weapons. Typically though, the stronger weapons such as light machine guns, Wunder Weapons, and shotguns have really slowed reload speeds.

Speed Cola allows for a quick reload, repairing barricades faster, and aiming down the sights faster. This combined with other perks such as Juggernog and Stamin-Up makes for the ultimate survival loadout, thus finishing the four main iconic Perk-A-Colas that have represented the whole perk system for years.

NEXT: 10 Best Video Games That Make Zombies Scary Again

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