- "A placeable dish that projects a cone of microwave radiation that stuns and impairs enemies."
- — Scorestreak description
It deals 10 damage to any players caught within its cone of radiation every 0.5 seconds (half a second), taking five seconds to completely kill an enemy in Core game modes at full health. The Guardian will slow enemies and impair their vision, and is easily distinguished by the particles emitted by its silver dish. The player gets 10 points every second for suppressing an enemy.
The Guardian is best placed at choke points, long and linear sightlines and to defend objectives while teammates are absent from the area. Hostile Guardians are highlighted in red when using the Engineer perk, making a combination of Engineer and Black Hat excellent when countering Guardians, as they can be easily hacked from behind cover where the player is safe from the wave it produces. However, the player should take care of their surroundings, as unexpected enemies can easily kill the player when hacking the Guardian, which takes approximately five seconds.
Guardians are extremely effective in Hardcore game modes, being caught in the guardian's microwaves results in almost instant kills. Unless your enemy has EMP Grenades or Black Hats, players can effectively block off tight corridors and limit their overall mobility across the map. It should be noted, however, that as of a recent patch, the Guardian's damage in Hardcore game modes has been reduced. Up to three Guardians can be placed by one player, or a combination of Guardians and Sentry Guns. A very effective tactic is to place two Guardians in a small corridor facing the same direction, while a Sentry Gun also faces down the same path of the microwave beams. This will render any incoming enemies unable to do anything while the Sentry Gun mows them down. However, this can be tricky on some maps, as not all maps have good spots for these two killstreaks. When used correctly, Sentry Guns and Guardians can work hand-in-hand to hold down a flag, bomb site or similar objective. Since up to three can be placed per player, if a team is coordinated, a building can be completley locked down with over 10 Guardians and Sentry Guns, rendering it almost impossible to enter without the proper tools to destoy said killstreaks, like EMP Grenades or Black Hats.
If one suspects there is an enemy Guardian nearby, but it is not in a clear line of sight, listen for the deep humming sound of the Guardian, or the visible distortion of the air in front of the Guardian. FMJ can aid the player in dispatching enemy Guardians through walls if the location of one is known.
Call of Duty: Heroes
- "Long range microwave emitter. Damages Ground targets and reduces their attack rate and movement speed."
- — In-game description
The Guardian reappears in Call of Duty: Heroes as the Guardian Turret, internally called the Microwave Emitter.
Call of Duty: Black Ops III
The Guardian, is a scorestreak featured in Call of Duty: Black Ops III. It requires a scorestreak of 750 to acquire. It functions the same as it's previous versions.
- When carrying the Guardian, a label on the back can be read "1.21 GW". This is a reference to the movie Back to the Future, where 1.21 Gigawatts are required to activate the Delorean time machine.
- When placed, a sticker on the rear can be seen that warns: "extended exposure may cause minor discomfort".
- The Guardian can kill dogs from the K9 Unit Scorestreak. When a dog is caught in the microwave beam, it will quickly topple over to the ground, only to keep trying to get up and chase the player, but it will keep falling over until it dies.
- The Guardian cannot destroy an RC-XD.
- The Guardian is referred to in the game files as the HPM.