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Collapse or Boss Chase (zs_bosschase) is a special Zombie Scenario "raid" map introduced in Zombie Scenario: Season 5.


Players are able to battle against several bosses from previous seasons. They are Oberon, Dione, Revenant, Fallen Titan, Neid and ZavistSiege Type Phobos and Frozen Terror, albeit as mini-bosses the last two.

Official description[]

Using the data collected from a secret laboratory, a secret Intelligence was founded to revive the bosses for simulation experiment.

Locate the place and defeat all the bosses before they have a chance to escape. Destroy the lab!


  • Find and eliminate all the bosses.

Release date[]

  • South Korea: 17 September 2015.
  • Taiwan/Hong Kong: 22 September 2015.
  • China: 23 September 2015.
  • Japan: 30 September 2015.
  • CSN:Z: 18 December 2015.
  • Indonesia: 3 February 2016.
  • Vietnam: 26 May 2016.


  1. Can you hear me? Thanks God if you are safe! Let’s start the mission briefing.
  2. Your mission is to launch an attack on the lab and eliminate all zombies.
  3. All the bosses are in recreated areas which mimic their original locations where they first appeared. Thry are called as "testing area".
  4. I believe the path to the next one will appear when you defeat the boss in the current area.
  5. The security is tight, so I can’t keep an eye on where you are located or where you’ll be heading next.
  6. So be cautious and complete the mission!
  7. The door to the next stage is open! Move!



  • This map introduces a new gameplay of Scenario: Raid. The main goal is similar to Annihilation style, eliminate all the bosses.
    • The differences are, instead of defeating each boss in each round, the game only consists one round, and players must find the arenas to defeat the bosses. In other words, this gameplay is a combination of Pursuit style and Annihilation style.
  • This map is a mixture of each boss arena, from Dead End, Toxicity, Decoy, Contact and Envy Mask. Note that the selection is random, the game can start at any 1 of them.
  • Defeating bosses in this map does not increase the counter of [Phobos Slayer], [Oberon Slayer], [Dione Pursuer], [Firefighter], [Titan Attacker] and [Detective] medals.
  • Players will face seperately Siege Type Phobos and Frozen Terror in a small area as mini-bosses that have to be defeated in order to proceed to the next area as they will block the way during breakthrough. Their behavior is akin to previous chapters - lower healthpoints and basic attacks, however, only Frozen Terror will be launching basic attacks.
  • If Round Retry is used, the game will not be restarted but continue as is currently, meaning that health points will not be affected. 
  • This is the second time where players are able to kill Dione after in Zombie Giant