Although not really useful, the game keeps count of how many zombies you kill in a row. While not advantageous in any way, think of it as bragging rights for your own personal use.
Here is a list of killstreak titles given in the order they would appear:
- First Kill / Nothing
- First Kill only appears once but is rather self-explanatory.
- Double Kill
- Triple Kill
- Quad Kill
- Multi Kill
- Crowd Control!
- Head Hunter!
- MEGA KILL!
- MASSIVE KILL!
- ROUND BREAKER!
- HUMAN NUKE!
- KING KILL!
- YOU ARE THE CURE!!
- There are no more titles after this and this title will just pulsate with every preceding kill.
- Explosives (such as the RPG or Grenade), incendiary items (such as the Flamethrower and Molotov) and automatic weapons (such as the Minigun and M249) can allow you to get a big headstart on your Killstreak.
- After every kill, you have 1-3 seconds to find another victim until your Killstreak resets.
- If your first kills are done instantaneously through explosives (for example Propane, Grenades, M202, etc.), the Killstreak will show according to the table shown above, but the First Kill killstreak will only show when you have your first single kill in the round.
- Only AIs that grant Cash upon death are counted towards your Killstreak.
- Prior to v1.3.3, Killstreaks were slightly different for Team Deathmatch and lasted until you die.
- As of v0.9.7, zombies can now obtain Killstreaks of their own.
- This is quite rare as zombies have difficulty getting more than two kills every 3 seconds.
- In v1.0.1, the visual UI was overhauled to have a new look.
- This feature was in R2D.