In addition, players can choose certain skill paths to master from.
As of 9 July 2015 update in South Korea, Zombie Crush was reorganized, adding new items and skills.
- Optional skills
Players can choose to use 1 optional skill when starting the game. The skills can not be changed during the game.
- Health Support: Drops several healthpacks in a small radius.
- Bombing Support: Requests an airstrike support at the desired point.
- Fitness Absorbing: During certain times, regains a certain percentage of stamina depending on the damage caused to enemies.
- Rampage: Attacks targets around randomly during certain times.
- Spreading Shot: During certain times, allows the player to attack nearby enemies around the main target.
Players can use items for battles. Choose a desired item in the store.
- Instant Resurrection: revives HP immediately.
- Recovery Capsule: recovers 30% of maximum health for five seconds ( key by default).
- CTU Funding: each time clearing the mission will receive an additional $10,000 in support from CTU headquarters.
- Automatic Turret: installs automatic turret to attack enemies ( key by default).
- Shield: during certain times, player can unfold a shield to reduce a certain amount of damage.
Because of the zombie virus, both Terrorist and Counter-Terrorist teams suffered a heavy blow. Moreover, the sign of the virus is expanding worldwide. So, the two teams decided to gather the strength for a preliminary cooperation to fight the zombies.
Searching, they discovered the host who causes the virus. To prevent the virus expansion, the only solution for both sides is making a task force which is composed by all elite factions to eliminate the host. Both sides of this mission, which named Zombie Crush, has decided Lincoln - director of CTU, to be the commander in charge of the operation. The host - Max, had acquired controlling the town; the coalition of CT and TR with the best agents from both teams were dispatched to the area.
Zombies attack both teams in this unprecedented mission... Zombie Crush began in earnest.
There is a metro station near the place where the host - Max causes the virus. The ceiling floor was destroyed because of the zombies.
Lincoln led the team to examine the subway, investigating whether the virus spreads out by any route. However, the crew fell into a trap. Lincoln tried to open the door, but it was not easy to control the unstable electric power of the station.
Now the crew must survive through the pouring raids of zombies from everywhere.
They traced Max to a closed underground space. Connecting to the ground through an entrance, this huge hall is Tesla Institute, where Z-virus was experimented. Following the secret information from a message left by the researchers, everything is revealed. The Z-virus experiment ended in failure, including the escape of Max.
Another fact revealed. The SS-grade host zombie, Tesla, has been released and trying to escape through the ceiling of the hall.
Tesla is the largest and strongest zombie they've ever seen so far. Surrounding with massive electric shock, it is the most powerful zombie to be created.
The force now is struggling in the battle with Tesla, in order to prevent it escaping, or it will be the end of the world.
Generally, it is nearly similar to the Zombie Scenario mode back in Counter-Strike Online. With the basic manual upgrade with dollars, the players can upgrade their firearms damage, melee damage, health, armor and magazine size with dollars which can be obtained by killing zombies.
There are several missions need to be accomplished by the players in a limited time. In comparison to Zombie Scenario, it is more interactive and has multiple types of task to be done, making the gameplay more realistic and fun. The tasks involve defence, evacuations and finally a boss battle.
- Can only start if there are at least 5 players in the waiting room.
- Other players cannot enter the room after the game has started.
- The maximum number of players is 8.
- During the first missions, if a player dies, he/she can only respawn in the next mission, or if all players are dead, the game will end. In boss mission (final round), each player will have 30 seconds to respawn if he/she dies.
to open the Upgrade tab. The skill that can be upgraded are:
- Bullet Damage ( ), max 30 levels.
- Melee Damage ( ), max 15 levels.
- Maximum Health ( ), max 20 levels.
- Armor Points ( ), max 10 levels.
- Bullet Capacity ( ), max 10 levels.
- Press to build a sentry gun. Each sentry gun has 70 seconds before it stops working automatically. Each player can build only 1 sentry gun for each usage. The new one can be built only when the previous sentry gun duration expires or it is destroyed by zombies.
- The players can check how many percentages of boss's HP they damaged on the boss's health bar. Also, each player can check other teammate's HP and their status (death or alive), which is shown below the screen.
- Players only have a limited amount of time to defeat the boss, depends on each chapter. Failing to do so results in a loss.
- South Korea: 16 February 2015.
- China: 1 July 2015.
- Taiwan/Hong Kong: 9 March 2016.
- The alarm sound heard in this mode is reused from Half-Life 2.
- The player can upgrade the magazine size of the weapon, which is not available in original Counter-Strike Online.
- Some interfaces and zombies are very similar to the ones in Left 4 Dead, another Valve's game.
- There is a part of the map where players are able to drive vans. Other players can become passengers to the drive to reach another part of the map.
- The music played during the boss battle is reused from one of the Big City trailer's music themes.