In Keros players can choose up to three killstreak rewards they can earn, rather than just the standard three. At the start, the player can only use UAV, Care Package and Predator Missile, with the option to unlock one new killstreak at each of the following levels: 10, 15, 23, 35, 47, 50 (all killstreak rewards will be unlocked at level 50). When a killstreak of 8 or more is activated, a message will notify all players in the match, showing the callsign and the streak being used (except in Hardcore or when the killstreak is a Stealth Bomber being deployed by the opposing team). Even though a plasma bombardment is announced to both teams, the player's callsign on the top-right corner will only be shown to players on that player's team.

It is worth noting that two killstreaks that share the same killstreak amount cannot be used together, one must be picked over the other. For example, for the 7 kills slot the player can use either the Harrier Strike or the Attack Helicopter, but not both.

For controllable killstreaks (Predator Missile, Chopper Gunner, AC130 and others), if the player is killed while operating the killstreak, the player can continue using the killstreak until it is done and then respawn or enter spectator mode as normal. The only exception to this is Search and Destroy. This outcome has been protested by some who feel the killstreak should end if the player dies.

If the players have aircraft on the map then all aircraft killstreaks will be disabled, except the plasma bombardment.

Kill Killstreak Reward Voice heard when activated Description

Enemies: Enemy UAV is online

Allies: Our UAV is online

Deploys a UAV to scan the map and reveal enemy locations. Can be shot down or hit with a Predator Missile.
2 Care Package

Enemies: Enemy is receiving a care package

Allies: Care package is on the way

Player must throw a red smoke grenade to mark the location of an air drop package containing a random killstreak or ammo. The package can kill players if it lands on them. Can be taken by anybody. It takes longer for anybody but the user to obtain the package, leaving them vulnerable.
2 Medical Package

Enemies: Enemy is receiving medical aid

Allies: Medical Aid is on the way

Player must throw a green smoke grenade to mark the location of an air drop package containing a medical package to heal a players shields or wounds. The package can kill players if it lands on them. Can be taken by anybody. It takes longer for anybody but the user to obtain the package, leaving them vulnerable.
3 Sentry Gun

Enemies: Incoming Sentry gun!

Allies: Sentry gun is on the way

Player must throw a blue smoke grenade to mark the location of an air drop package containing an M5 Minigun configured as an automatic sentry gun. The same rules for the care package apply. A single slash from a knife will disarm it. Has a time limit.
3 Counter UAV

Enemies: Our UAV is offline

Allies: Counter UAV is activated

Deploys a UAV that disables the enemy's radar and renders hostile UAVs useless. Can be shot down or hit with a Plasma Predator Missile.
4 Plasma Predator Missile

Enemies: Enemy Predator is online

Allies: Your predator missile is on standby

Fires a single controllable AGM Hellfire from a Plasma Predator Drone that results in a deadly impact kill. The user is vulnerable while using/controlling the missile.
5 Communication Network Disabled

Enemies: Our Communications Network is disabled

Allies: Enemy's Communications Network is offline

Using satellite, enemies voice headset will be muted for 30 seconds.
6 Precision Airstrike

Enemies: Incoming Airstrike...take cover!

Allies: Airstrike incoming

Initiates an airstrike on a targeted area much like the Airstrike in Call of Duty 4. The user can control the direction from which the airstrike comes.
6 B1 Lancer

Enemies: B1 Lancer is on the way!

Allies: B1 Lancer is on standby

Deploys a small airstrike followed by a B1 Lancer that will fly over the designated area throught the map and bombard enemies. Can be destroyed. Will disperse rockets and destroy Pave Lows and other Helicopters or Planes that are lower than the B1 Lancer.
7 Troop Drop Zone

Enemies: Troops incoming!

Allies: We have reinforcements!

Deploys up to 10 troops (depending on your species and armor your wearing) to engage the enemy. Difficulty is Legendary and they are tactical. When the player calls in for troops, they troops will look exactly like the player that called them in. Not available for system link, or Xbox Live.
7 Attack Helicopter

Enemies: Enemy attack helicopter is on the way!

Allies: Attack helicopter is ready for engagement

Deploys a Hind or Cobra helicopter armed with a single 25mm gun that flies around the map and attacks enemy players. Can be destroyed. Non-Pilotable.
8 Emergency Drop

Enemies: Enemy Emergency drop is on the way

Allies: Emergency drop is ready for deployment

Deploys a C-17 Globemaster III that drops four Care Packages. Can be stolen, but C-17 Globemaster III cannot be destroyed. it is interesting to note that the emergency airdrop will not work in an EMP.
9 Pave Low

Enemies: Pave low is on the way!

Allies: Our pave low is ready for deployment!

Deploys a Sikorsky MH-53 Pave Low armed with four 25mm guns. The Pave Low is essentially a better version of the Attack Helicopter. Can be destroyed.
9 Heavy Assault Tank (2X Overshields)

Enemies: Incoming...Heavy Assault Tanks...take them out!

Allies: Our Assault tanks are moving out!

Deploys a heavy assault tank equipped with tow overshields, Cannot be driven. Can be destroyed.
10 Stealth Bomber

Enemies: Infrared has detected an incoming stealth bomber!

Allies: Stealth Bomber taking off

Deploys a B2 Spirit that is invisible to the enemy's radar. The bomber carpet bombs a specific line, designated by the player.
11 Chopper Gunner

Enemies: Enemy Chopper gunner! Get down! Get down!

Allies: Chopper gunner is taking off, engage all enemy hostiles

Deploys a AH-64 Apache or Mi-28 Havoc attack helicopter with the player firing from a turret. The player CAN BE KILLED on the ground, but, can still finish out the session in the chopper. This killstreak can be destroyed by means of rocket launchers, guns, or with a predator missile.
13 AC-130

Enemies: Enemy AC-130! Get down! Get down!

Allies: AC-130 has been launched. Engage all enemy hostiles, light them up

Deploys an AC-130 controlled by the player on the ground. The user is vulnerable while using the gunship. Can be destroyed by a launcher or at least 2 predator missiles. It has 4 flares meaning at least 5 rockets must be shot. Player gets the options to use the minigun, 40mm/25mm cannons, or the 105mm cannon.
15 EMP

Enemies: EMP! Take Cover!

Allies: EMP is activated!

Deploys an electromagnetic pulse that destroys enemy killstreaks and disables enemies' HUDs, Radar, and other electronic Attachments or Equipment that enemies may use, along with, Throwing Knives.
20 Scarab Assault

Enemies: Enemy Scarab! Take it down with minimum health loss!

Allies: Our Scarab is ready for assault!

Deploys a Scarab to destroy the enemy. It is invulnerable to the plasma predator missile, Pelican or Phantom gunner, Stealth bombers, and other explosion equipment. The only way to take it down is by weakening the legs, going in, and destroying the central core.
25 Plasma Bombardment

Enemies: Carrier Incoming!!!!!

Allies: Our Carrier is ready for bombardment. Orders sir!

Deploys a assault carrier, and glasses the map resulting in a game over.