Killstrikes
UAV

Unlike in Call of Duty 4, UAVs fly around the map, so they can be shot down. They are rather weak, so it's better to use your primary weapon rather than wasting a valuable missile on them. Players using the Cold-Blooded perk won't show up on the radar.
# 4 Kills
Care Package

Care Packages can be seen on the radar by everyone. It's marked green if it's friendly, otherwise red since it belongs to the enemy team. Care Packages, Emergency Airdrops and Tactical Nukes can't be acquired from the package. Below are the drop rates:
14.78% - Ammo
14.78% - UAV
13.04% - Counter-UAV
10.43% - Sentry Gun
10.43% - Predator Missile
9.57% - Precision Airstrike
6.09% - Harrier Strike
6.09% - Attack Helicopter
4.35% - Pave Low
4.35% - Stealth Bomber
2.61% - Chopper Gunner
2.61% - AC-130
0.87% - EMP
Counter-UAV

Counter-UAVs fly around the map, so they can be shot down just like regular UAVs.
# 5 Kills
Sentry Gun

The Sentry Gun has a 180 degree turn on its turret and can pitch up and down, but it can't detect players using the Cold-Blooded perk. They are most effective when placed in high places.
Sentry Guns can be temporarily disabled with Flashbangs and Stun Grenades. Normal weapons don't do much damage to it, so use explosives instead. You can instantly destroy them with a melee hit or a Throwing Knife - silly, but true. The turret can over-heat if it's fired for too long, so use that to your advantage. The Sentry Gun will disable itself after 90 seconds.
Predator Missile

Enemies that don't have the Cold-Blooded perk will appear with a red box around them. The Predator Missile has a moderate explosion radius, so you don't need to hit the enemy dead-on. You can also use it to take down enemy helicopters and harriers.
You are vulnerable while controlling the Predator Missile, but if you get killed on the ground, you can still continue your missile attack.
# 6 Kills
Precision Airstrike

# 7 Kills
Harrier Strike

This basically combines the Airstrike and Attack Helicopter to one neat package, but the harrier doesn't circle the map, it just stays still. Harriers can be destroyed with one stinger/javelin missile.
Attack Helicopter

Attack Helicopters can be destroyed with one stinger/javelin missile.
# 8 Kills
Emergency Airdrop

Try to avoid situations where the packages land outside the map. The plane always comes from the opposite direction you're facing (when throwing the red signal flare) and flies in a straight line.
Care Packages, Emergency Airdrops, EMPs and Tactical Nukes can't be acquired from the packages. Below are the drop rates:
12% - Ammo
12% - UAV
16% - Counter-UAV
16% - Sentry Gun
14% - Predator Missile
10% - Precision Airstrike
5% - Harrier Strike
5% - Attack Helicopter
3% - Pave Low
3% - Stealth Bomber
2% - Chopper Gunner
2% - AC-130
# 9 Kills
Pave Low

The Pave Low also has chaff (1 set) as a countermeasure, so the first locked-on missile won't hit it.
Stealth Bomber

The airstrike doesn't show on enemy radar.
# 11 Kills
Chopper Gunner

The 25mm gun doesn't need to be reloaded, so you can easily kill multiple enemies. Enemies that don't have the Cold-Blooded perk will appear with a red box around them. You are also vulnerable while using this killstreak, but if you get killed on the ground, you can still continue your session.
The helicopter has 1 set of flares, so the first locked-on missile won't hit it.
AC-130

Enemies that don't have the Cold-Blooded perk will appear with a red box around them. You are vulnerable while controlling the AC-130, but if you get killed on the ground, you can still continue your session.
The AC-130 can only be shot down with missiles, but it has 2 sets of flares as countermeasures, so the first 2 missiles won't hit it.
# 15 Kills
EMP

The EMP also has the following effects on the enemy:
- Removes the heads-up display, HUD.
- Disables electronic sights.
- Red Dot Sight, Holographic Sight, Thermal Scope etc.
- Heartbeat Sensors won't work.
- Disables Sentry Guns.
# 25 Kills
Tactical Nuke

Once activated, nothing can stop it.