Counter Strike Online Indonesia Wiki
Bosshp bg left zombiejack
I become like this all because of you.
- Jack's words in Memories chapter

Jack is a boss in Memories chapter in Counter-Strike Online.


Zs memories3 cso

Jack was one of the escapees from Rex Laboratory after the zombie virus outbreak incident alongside Jennifer. Unfortunately, he failed to escape while on the go and suffered from the zombie virus, mutating into an evil abomination seeking for revenge with Jennifer becoming one of his targets for the lost cause.


  • Normal attacks:
    • Ground punch
    • Direct punch
    • Slash
  • Warp attack: Move instantly to the target and attack.
  • Toxic jump: Jump to higher place and flood the lower area with toxic. The player must find the indicated pipe to flow away the toxic.
  • Shock wave: Send a harming sound wave to the target.
  • Shoots with an M134 Minigun Predator
  • Rocket throwing

Recommended weapons[]



  • The boss's model resembles some characters in other game, especially Resident Evil series.
  • This is the third Z-Virus mutant that is able to gain consciousness after Dr. Rex and Laser Wing.
  • When the boss is doing rocket and minigun attacks, he is invulnerable to any damage. This is probably to avoid possible bug where the boss is dead while he's in unreachable area.
    • However, there is a bug where if a player uses Bendita to shoot Jack when he is using rocket or minigun, he/she still can damage him.
    • There is another bug where sometimes when Jack jumps on to the high place of the boss room, he will be stuck (cannot jump down), which makes him "invulnerable".
    • Nevertheless, some previous bosses also have "vulnerable time" but they are not flashed with white cover.
  • Some skills of the boss may be an inspiration from Goku's skill from Dragon Ball series, most noted with the Instant Transmission and Kame Hame Ha skills.