Zombie scenario

Zombie Scenario is the second game mode introduced by NEXON Corporation for Counter-Strike Online based on a custom game mode for Counter-Strike known as Zombie Riot.


Zombie Scenario pits up to 10 players against increasingly hordes of AI-controlled Zombies. Money cap is doubled in this scenario and the amount obtained varies between types of zombies killed and the difficulty of the map. Extra health, damage and barrier durability can also be bought off the buy menu if the player have obtained a sufficient amount of money. The rounds will keep getting harder with different powerful zombies spawning in.



ZScenario reboot banner

Zombie Scenario is included in the Re:boot update, which completely overhauls its old system and adds new features :

  • Difficulty level
  • Automated firepower, health points (with partial restoration) and armor upgrade upon levelling up
  • Rewards after annihilating bosses
  • Buy menu/check point improvement
  • Adjusted respawn time for players of different levels
  • Added character stats

  • Entry level: Entry level is Easy/Normal/Hard. Be able to choose difficulty level that suits for each player’s skill to make them to enjoy zombie scenario in a comfortable environment. Reward will be different according to the difficulty level.
  • Dynamic difficulty level: A difficulty level that continues to change in the game according to the player’s play. Provides high level of exciting game play to skillful user. Reduce stress with low difficulty level from unskillful user.

  • Provides a rank to user when they cleared a scenario according to their participation and contribution rate.
  • Induce a repeatable game play from user by providing a challenge goal to them except the difficulty level and clear time.
  • There are 5 stages of rank from D to S.
    • Can obtain every rank regardless of its entry level.
    • Give different rank to player with their individual play.
  • Indicate the rank and provide the reward together in game when they clear the scenario.
Result rank Reward
Result rank d Result rewardbox d
Result rank c Result rewardbox c
Result rank b Result rewardbox b
Result rank a Result rewardbox a
Result rank s Result rewardbox s

  • Auto Upgrade: Does not require extra key control, and upgrade it automatically with zombie kill, boss and breakable attack.
  • Upgrade target added: HP, attack, armor, movement speed and ammo.
  • Different max level and upgrade sequence for each class, max level increased by 100.

  • Obtain reward when user clear the game according to its difficulty level and rank. Consists of scenario exclusive item, point item, and cash item.
  • Add scenario exclusive buff item according to upgrade target increase.
  • Functional costume and tattoo will appear as unique reward. It will only effective in scenario and no effect in other game mode.
  • Note: all rewards before Re:boot cannot be obtained anymore.

Highzsbox Levelupamplifier

  • Care a beginner user and provide convenient of purchase to previous user. Reduce difficulty of purchase weapon by recommending weapon to beginner user. Add a new purchase method of favorite menu to provide convenient to previous user by considering their game control.
  • Recommendation Weapon: Can purchase recommended weapon with F1 after entering the buy zone. Only main weapon will be recommended.
  • Buy menu improvement: Favorite menu added in buy menu UI. Reduce user’s time to purchase their favorite weapon.
  • Add weapon detail information menu in buy menu. Add shop information to help them to select a weapon.

  • Feedback UI added for user play when they play scenario.
  • Indicates Perfect when they succeeded in headshot.
  • Indicates Combo when they succeeded to kill enemy in consecutive shot.

  • Allowed activity when a player is dead:
    • Chat with survivors: Share pursuit, boss pattern with survivors.
    • Can purchase weapon or equipment: Can rearrange the weapon with B button when you die. Purchase standards will based on the current possessed dollar. Dollar will not deduct directly after purchasing, but it will be deducted when a player revives and the item will provide together.
  • Adjust revival time per level: Allows beginner or low level user to quickly re-participate in the battle to play the game easier than before.
Level Revival Time
1 - 10 15
11 - 20 20
21 - 30 25
31 - 40 30
41 - 50 35
51 - 60 40
61 - 70 45
71 - 80 50
81 - 90 55
91 - 100 60

Characters and Factions now have different stats in term of:

  • Health.
  • Attack.
  • Mobility.
  • Kevlar Armor.
  • Spare Ammo.

Name Health Attack Speed Armor Ammo Max Level
Kal-El 25 23 21 28 18 115
Aetheris 26 23 21 26 19 115
Transcendent Fernando 26 24 21 26 18 115
Sonya Lycanthrope 28 24 26 22 15 115
Transcendent Choi Ji Yoon 24 18 26 28 19 115
Dorothy Dark Knight 24 27 23 22 19 115
Lisa 26 22 18 26 18 105
Victor 26 21 16 25 17 105
Ian 21 23 24 17 20 105
Rebecca 24 21 19 21 20 105
Dr. Han 25 22 17 20 21 105
Ha Ly 20 21 23 23 18 105
Soy 18 22 20 21 24 105
Dominique 21 26 19 24 20 110
Henry 21 20 20 23 21 105
Isabelle 21 27 20 21 21 110
Choi Ji Yoon (Limited Edition) 20 20 24 24 17 105
Choi Ji Yoon (Soccer) 22 17 24 26 16 105
Choi Ji Yoon 22 16 24 26 17 105
Natasha (Casual) 21 25 20 22 17 105
Natasha 21 25 20 22 17 105
Alice (Limited Edition) 22 19 19 26 19 105
Alice 22 19 19 26 19 105
Lucia 24 23 18 18 22 105
May 21 25 20 22 17 105
Criss 26 21 20 17 21 105
Walter 25 17 17 23 23 105
Enzo 24 22 18 21 20 105
Fernando 25 22 19 19 20 105
Keith Icahn 18 24 19 23 21 105
SAF Scout 18 19 26 24 18 105
Max Thacker 20 25 19 22 19 105
Gerard 18 24 21 19 23 105
Thunder Squad 20 19 18 24 24 105
SAT 19 17 22 25 22 105
PLA 17 19 23 23 23 105
707th Special Mission Battalion 22 24 17 23 19 105
Spetsnaz 24 20 18 24 19 105
GIGN 21 21 21 21 21 105
SAS 21 21 21 21 21 105
GSG-9 21 21 21 21 21 105
Seal Team 6 21 21 21 21 21 105
Medea 22 26 28 19 20 115
Axion 24 26 26 19 20 115
Rose Phoenix 26 25 22 22 20 115
Transcendent Blair 24 26 26 21 18 115
Transcendent Michaela 21 25 25 19 25 115
Elizabeth Crimson Hunter 19 24 28 18 26 115
Transcendent Yuri 19 28 25 22 21 115
Flora Paladin 27 24 22 23 19 115
Mila 22 26 26 18 18 105
Yuwei 24 23 21 17 20 105
Ace 21 23 19 22 20 105
Jenny 22 25 20 18 20 105
Krieg 20 24 20 20 21 105
Jim 20 26 17 22 20 105
Alin 21 23 26 19 21 110
Gunsmith 20 22 22 20 21 105
Lingling 26 20 20 23 21 110
Michaela (Limited Edition) 17 26 18 20 24 105
Michaela 18 25 21 19 22 105
Jennifer (Uniform) 22 26 22 17 18 105
Jennifer 22 26 22 17 18 105
Yuri (Soccer) 17 26 23 20 19 105
Yuri (Limited Edition) 17 26 23 20 19 105
Yuri 17 26 23 20 19 105
Blair 20 26 22 21 16 105
Ritsuka 16 23 26 17 23 105
Erika 26 17 19 23 20 105
Carlito 25 22 22 18 18 105
Raven 26 20 23 18 18 105
Spade 17 23 22 17 26 105
David Black 25 19 18 21 22 105
Vigilante Corps 24 19 22 20 20 105
National Liberation Campaign 16 17 24 24 24 105
Asia Red Army (Soccer) 21 18 24 18 24 105
Asia Red Army 21 18 24 18 24 105
Red Beret Condottiere 19 24 21 20 21 105
Midwest Militia 21 21 21 21 21 105
Guerilla Warfare 21 21 21 21 21 105
Arctic Avengers 21 21 21 21 21 105
Elite Crew 21 21 21 21 21 105
Phoenix Connexion 21 21 21 21 21 105

Z-Noid patch

After 28 January 2016, there are several update:

  • The addition of 12 difficulties: Easy 1 & 2, Normal, Hard 1-9.
  • Different difficulties give out different Daily ZS Clear Rewards.
    • This reward can only be obtained twice per day; once every 12-hours interval.
    • The player can choose what prize to be claimed. It ranges from common to rare items such as rare zombie tattoos and costumes.
    • The Reward Box can be upgraded. If the player obtains a box at low difficulty level, and does not use it yet, then he/she plays another game (in the same day) and obtains higher-leveled box, the higher-leveled box will replace the lower one.
  • The players can now earn dollars and level up by just shooting at the zombies.
  • If the player uses Round Retry item, all players will respawn immediately, instead of running the round all over again.
    • However, all players just have 1 chance to retry, no matter who use the item. If the players still loose the second chance, the game will end.
  • The respawn time has been set to a limit of 120 seconds, increasing as players level up.
  • Zombies are now labeled with a new set of colors to identify their behaviour, they will be common in the hardest difficulties.
  • Removed items: Dr. A's Trunk, Secret Map, Research Tools, Zombie Sample and Confidential Documents.
  • Fixed some bugs.

As previously stated, players are able to obtain a Reward Box twice per day upon successfully finishing a Zombie Scenario map. The amount of items, duration, quality, quantity and rarity is based on the box level.

The following items can be acquired:

Reward Box HARD 9 level

CSO TW HK - Zombie Scenario TRAP - HARD9

CSO TW HK - Zombie Scenario TRAP - HARD9

2018 Reboot

Scenario reboot result

End result interface

Zombie scenario reboot balance modification (applied to Last Clue, Panic Room, Omen)
  • You can't share/drop weapons in HARD difficulty (the dropped weapons will instantly dissapear).
  • In HARD 3 and above, zombie boss skills have been given an instant kill attribute.
  • You can resist boss skills through resistance cues.
Zombie scenario reboot additional compensation (applied to Last Clue, Panic Room, Omen)
  • Parts from the Part System can be obtained in HARD modes.
  • An optional parts box is added to existing daily compensation.
  • Excellent rewards will be paid to the best players .

2018 Reboot Part 2

Possible obtainable parts
In HARD 9, obtaining Tier 6 Parts are possible.
Map Possible parts
Last Clue Hold Up Vampire Armor Break
Panic Room Rage Down Speed Up Slow
Omen Knockback Power Up Healing Cancellation
All-Out Health Up Gun Boost Critical

Zombie Scenario Clue Items

Icon Name Effect
Zbs fundplus Secret Research Funds Given fund: $32,000 (Initial fund: $7,500)
Zbs lvplus Level Up Amplifier Obtain additional experience
Zbs attplus01 Attack Amplifier Attack Strength Auto Upgrade. (If you have the same type of clue, only the upper level is applied.) Inferior: 3 stages, Intermediate: 5 stages, Superior: 7 stages.
Zbs hpplus01 HP Supplement Stamina Level Auto Upgrade. (If you have the same type of clue, only the upper level is applied.) Inferior: 3 stages, Intermediate: 5 stages, Superior: 7 stages.
Zbs armplus01 Bulletproof Armor Armor Upgrades. (If you have the same type of clue, only the upper level is applied.) Inferior: 3 stages, Intermediate: 5 stages, Superior: 7 stages.
Zbs spdplus01 Combat Boots Move Speed Auto Upgrade. (If you have the same type of clue, only the upper level is applied.) Inferior: 3 stages, Intermediate: 5 stages, Superior: 7 stages.
Zbs magazineplus01 Spare Magazine Preliminary magazine stage auto upgrade. (If you have the same type of clue, only the upper level is applied.) Inferior: 3 stages, Intermediate: 5 stages, Superior: 7 stages.
Zbs fundcollection Money Extractor 1.5 times increase in earned dollar (Initial salary: 7,500)
Zbs weakpoint01 Weakness Analyzer Additional damage to Zombie Boss (Initial Salary: 7,500)
Zbs ttsnake Snake Tattoo Attack Strength Max Level 3, Stamina Max Level 2 Stage Increase
Zbs ttpoisonfire Poison Fire Tattoo Stamina, ATK, Movement Speed, Armor, Shoot Level 1
Zbs ttsnow Snow Tattoo Increased maximum damage level by 5
Zbs ttrustyscorpion Rusty Scorpion Tattoo Attack power Max level 3, Move speed 2 level increase
Zbs ttmadmechanic Mad Mechanic Tattoo Stamina Max Level 2, Armor Max Level 3
Zbs ttgluttony Gluttony Tattoo Up to 5 health levels
Zbs ttzavistneid Neid and Zavist Tattoo Stamina Max Level 3, Damage Max Level 2 Stage Increase
Zbs ttphobos Phobos Tattoo Armor Max Level 3, Shotgun Max Level 2 Stage Increase
Zbs ttdione Dione Tattoo Movement speed Max level 5 steps increase
Zbs lastclue boss Phobos Attack Withstand Able to withstand some attacks in Last Clue.
Zbs panic middleboss01 AMP Suit Attack Withstand Able to withstand some attacks of AMP Suit in Panic Room.
Zbs panic boss01 Kraken Attack Withstand Able to withstand some attacks of Kraken in Panic Room.
Zbs evacuate boss01 Laser Wing Attack Withstand Able to withstand some attacks of Laser Wing in Omen.
Zbs allout boss Colossus Attack Withstand Able to withstand some attacks.
Zbs cosoberonhead Oberon Horn Critical hit increase 3%
Zbs cosoberonbombhead Oberon Bomb Head Shockwave resistance with a 20% probability
Zbs cosangraback Angra Wing 25% increase in jump
Zbs costitanback Fallen Titan Doll Resurrected with 100 Stamina in Death Crisis
Zbs coskrakenback Kraken Back Ignore 20% chance traps
Zbs cosfrozenwrathback Frozen Terror's Club Damage reduced by 25% when blowing
Zbs cosjackmaskface Jack's Mask Face 20% reduction in stiffness when hit
Zbs cronobotics53 face Crono Athletic's Face Increased Critical 4%
Zbs cronobotics54 back Crono Wing's Wing 20% jump and 20% drop damage
Zbs mr x zb back Mr. X's Back Slow speed recovery
Zbs cosbrachyuraback Tyrant Crab's Back 3-step automatic upgrade of body armor
Zbs cosgrasshopperback Laser Wing's Wing Jump force 20% Movement speed 1 step increase
Zbs zbombdown Venom Guard Damage Down Reduce explosion damage by Venom Guards.
Zbs zboomdown Zombie Grenade Damage Down Reduce explosion damage by Zombie Grenades.

Crazy Zombie Scenario event

This is a special event which is applied for Memories chapter:

  • Only applied for Memories map during event period.
  • Player's movement speed is increased, and be provided with unlimited spare ammo.
  • Every 60 seconds, up to 3 Pierrots will summon randomly.
  • After destroying the Pierrot, 5 random bonus weapons will be dropped randomly.
  • Bonus weapons can be used in event map only and will not be saved into inventories.
  • All relating medals and league score are not counted in this event.
Counter-Strike Online China Trailer - Memories (Special)

Counter-Strike Online China Trailer - Memories (Special)


There are 7 seasons so far in Zombie Scenario mode (noted that extra maps are excluded in the chapters below):

Survival type
Chapter Description
Lost city icon Story of the special force squad that has been dispatched to find a research group that has lost contact. Goal: Fight against the zombies and survive until the last round.
Double gate icon Survival stage for those survivors in the special force. Goal: Fight against the zombie and survive until the last round.
Trap gfx The last hint left by the special force squad. It seems that they found another trace, but as soon as they get into they are surrounded by zombies. Goal: Fight against the zombie and survive until the last round.
Pursuit type
Chapter Description
Lastclue icon Story of the special force squad that has been dispatched to save the advanced troop. Unknown huge monster was waiting for them when they arrived at the place after following the Andrey's clue. Goal: Kill Prototype Phobos.
Chaos gfx The research group entered inside the laboratory with the mysterious woman's help, encountering yet another monster again. Goal: Kill Siege Type Phobos.
Deadend gfx The research group received a support request from the allied forces and move to the appointed place to defend. However, the thing that welcomes them in the place was not the allied forces but Oberon. Goal: Kill Oberon.

Chapter Description
Zs trace cso Story of LS troop that received a request from Aegis Institute. They have dispatched to Southern America that assumed to have Dr. Rex's trace and... Goal: Kill Dione.
Zs culvert Story of LS troop that pursuits for wounded Dione. They entered underground culvert to capture Dione and encounter with countless zombies. Goal: Fight against the zombies and survive until the last round.
Zs decoy cso Senior Researcher Soy recognized that zombies will evolve by themselves and she tried to lure Dione in, however, the thing appeared in front of LS troop was not Dione, but that was great energy of fire. Goal: Kill Revenant.
Zs angra cso The last battle with Dione. LS troop found Dione's hideout and tried to kill defenseless Dione, but, soon a complete type Angra appeared in front of them. Goal: Kill Angra.

Chapter Description
Zs contact cso Story of Vanguard Company's assistant chief of staff for operations, Norman who tried to survive from a laboratory where a mysterious virus spread. Goal: Kill Fallen Titan.
Zs behind cso Story of David Black and Erika who tried to invade inside Vanguard headquarters under Norman's request. Goal: Kill Rusty Scorpion.
Zs defense cso Story of AFC David Black and his team retreating as they are being chased by horde of zombies until they reach into a shelter-like place. Unknown enemy appeared at them when they were waiting for Norman's support. Goal: Defend the central computer and kill Mad Mechanic.
Zs panic cso Story of David Black who tried to rescue Erika who was kidnapped by Norman. Analyze the huge boss's weakness that stopped their way to save Erika. Goal: Kill Lost Guardian.

Chapter Description
Zs encounter cso Story of Gerard team who tried to retrieve the left sample after the Vanguard Company incident. They tried to make a contact with the transportation team, however Yeti suddenly appeared to stop them. Goal: Kill Frozen Terror.
Zs conspiracy cso Story of Gerard when he was moving to meet with his client after he joined the Jim's transportation team safely. The client welcomed them frigidly in the laboratory. Goal: Kill Gluttony.
Zs envymask cso Story of Red Lizard Jim to discover and reveal the true color of the client. Goal: Defeat the dual-wield sword Neid and heavy artillery Zavist.
Zs paranoia cso Story of Red Lizard Jim, Gerard and their team upon revealing the mystery that Dr. Rex has been hiding once infiltrating into his main research lab and testing facility. Goal: Kill Dr. Rex.

Chapter Description
Zs evacuate1 cso Story of Jennifer and her escorts fighting their way through a long abandoned city, searching and destroying anything that they came across with what may remain of one of Dr. Rex's previous failed Super Soldier Project. Goal: Kill Laser Wing.
Zs memories1 cso Story of Jennifer and her team proceeding to pursue the Laser Wing killer. During that, she was unconscious, and remembered all her lost memories. Goal: Kill Jack.
Zs anothertruth1 cso Story of Jennifer finding out how Jack changed his appearance and the abandoned truth behind. Goal: Kill Crono Athletic.
Zs lastride1 cso Story of Jennifer encountering a new enemy while listening the truth from Soy. Goal: Kill Crono Wing.

Chapter Description
Zs mschoi1 cso Story of retrieving Choi Ji Yoon after being captured by a terrorist group. Goal: Kill Mr. X.
Zs victor1 cso Story of the disappearance of Victor's squad during the transportation of Phobos' DNA in Desert Storm operation area. Goal: Defeat Condemned Criminal.
Zs lusia1 cso Douglas Jacob is trying to convince the virus and to reinforce his influence Story of Lucia struggling in raids as part of its expansion. Goal: Kill Tyrant Crab.
Zs carlito1 cso Story of Carlito from his days with the Vanguard Company and how he lost an eye while escaping. Goal: Kill Jay.

Chapter Description
Totalwar1 With the surviving forces of the government and the Aegis Institute, Carlito's mercenary unit emerges as a new presence. Carlito's vengeance comes at a time when Kronos's one-sided contract breaks out. Goal: Kill Colossus.
Zs rendezvous1 cso The Lucia fleet captures repeated signals that are transmitted. Following the signal, she finds an unidentified facility on the way and instinctively begins a search operation with intuition that she is associated with Michaela. Goal: Defeat Kronos's Megalodon.

Honor missions

Mission Task
Finish Zombie Scenario season 1 to 3 in order.
[Killing Machine]
Kill 10,000 zombies in one round.
Kill a total of 1,000,000 zombies.
Pointbox medal
[Treasure Hunter]
Accumulate 100,000 points from Zombie Scenario Supply Box.


  • In Japan region, this mode is named as Zombie Survival.
  • Pressing the Auto-Buy button (F1) will select the most recommended primary weapon including its ammunition. Unlike normal matches, Kevlar is not included for Auto-Buy inputs even the player has still remaining in-game money which sufficient to spent for.
  • It is possible to apply wallbang for killing zombies or breaking a marked wall through some certain positions.

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