You earn streak points by taking out other players, but it isn't the only way to earn them. Taking out enemy Killstreaks and completing objectives in different games modes also score you points. In Capture the Flag, for example, you're better rewarded for capturing the enemy flag than engaging enemies.
Your points are reset upon death. You can accelerate your earned score with Seraph's (Specialist) Combat Focus ability.
HC-XD
Remote-controlled Hover-Capable Explosive Device with a charge that can be detonated at any time. The HC-XD can perform a thrust-powered jump and drive on walls.
Available at Rank 9
Streak Cost:
400
UAV
Unmanned Aerial Vehicle that periodically sweeps the radar and reveals enemy locations as dots. Can be shot down.
Available by default
Streak Cost:
425
Care Package
Airdrops a Care Package to the selected location. The package contains a random killstreak.
The Care Package can be hijacked and booby trapped by the enemy if left unattended.
Available at Rank 12
Streak Cost:
550
Counter-UAV
Jams the enemy radar and gives your team a slight information advantage. Can be shot down.
Available at Rank 27
Streak Cost:
575
Dart
Anti-personnel drone equipped with three lock-on missiles. This is player controlled, unlike the AI controlled Hunter Killer killstreak from Black Ops 2.
Once you lock-on to an enemy player or Scorestreak, you can fire a missile that seeks out the target. The Dart can also dive bomb for an explosive blast.
Available at Rank 18
Streak Cost:
600
Guardian
The Guardian places a microwave dish that can stagger, stun, disorient, and eventually kill any enemy that comes into range of the microwave beam.
Available at Rank 36
Streak Cost:
650
Hellstorm
Remotely launched precision missile with booster rockets. Comes with a cluster bomb payload that can be deployed to strike a wider area. Hellstorm is ideal for hammering key objectives, like control points in Domination.
Available by default
Streak Cost:
700
Lightning Strike
Launches a coordinated airstrike on three targets of your choice. You can do one UAV sweep to make your airstrike more accurate.
Available at Rank 42
Streak Cost:
750
Rolling Thunder
Deploy a targeted explosive drone bomb strike.
Available at Rank 21
Streak Cost:
900
Talon
AI or player controlled escort attack drone with a minigun.
Available by default
Streak Cost:
975
Cerberus
Airdropped into the selected location where it will automatically patrol and engage enemies. Can be player controlled at will.
The Cerberus is equipped with a powerful machine gun and rockets.
Available at Rank 49
Streak Cost:
1000
Wraith
Calls in a friendly attack craft with advanced stealth capabilities. Has a defensive flak drone to ward off enemy missiles.
Available at Rank 39
Streak Cost:
1100
H.A.T.R.
Gives your team the perfect surveillance of the entire enemy team with their exact locations and the direction they are facing.
The H.A.T.R. isn't orbital, but it can only be shot down by launchers.
Available at Rank 30
Streak Cost:
1150
R.A.P.S.
Airdrops multiple Robotic Anti-Personnel Sentry drones to the map that assault the enemy team like the K9 Unit killstreak from BO2.
Available at Rank 15
Streak Cost:
1275
Power Core
Once the device has been deployed it disables enemy electronics and cripples their thruster-assisted movements. The Power Core can be destroyed.
Available at Rank 33
Streak Cost:
1300
G.I. Unit
Heavily armored Juggernaut robot with an LMG. Can be set to patrol mode where it will defend a designated area. You can also set it to guard mode where it will follow and protect you.
Available at Rank 24
Streak Cost:
1550
Mothership
Powerful VTOL gunship with one primary and two secondary turrets. Delivers massive destruction with its powerful machine guns and rockets.
Teammates can join in and take control of the secondary turrets, as long as they haven't been destroyed. The Mothership can take a lot of damage before it goes out of commission.
Available at Rank 45
Streak Cost:
1600
