Once again, Counter-Terrorist and Terrorist must co-op to face a new enemy called the Joker (Mr. Hidden in some versions). This mode is only playable in its exclusive map, Harlem (Hidden City in some regions) with a maximum of 10 players in a match.
This is a Team Deathmatch-based mode but with humans vs Joker. In a round, a player will be randomly chosen as the Joker. The Joker is nearly-invisible on the start and loses his stealth after a few seconds. He is completely visible when attacking and will regain his invisibility when he successfully killes a human. He is only armed with a staff. In addition, he has high moving speed and jump, 300 health points and 100 armor points.
For humans, the humans must annihilate the Joker. The player that succeeded to kill the Joker will become the next Joker.
- Two primary attacks are needed to kill a human while the only a single secondary attack is needed to kill a human but with 1 second attack delay.
- Do not swing the staff too much as it will reveal yourself.
- Do not get close to smoke because your invisibility can be revealed easily.
- Strike from behind with secondary attack.
- Do not be greedy to kill humans. If the camping spots have 3 or more people, do not eliminate them if they already spotted you.
- Hit-and-run is the best tactic as a group of alert humans can easily spot and kill the Joker.
- Humans are recommended to stick together and notice the surrounding, report to your team if spotted the hidden.
- He is nearly invisible not fully invisible.
- Snipers are recommended if all of the humans has hold each of their position. M82, M24 and XM2010 are recommended because they are accurate when move-while-firing. However, they are weak when the Joker is close enough.
- Shotguns are also a threat to Joker if they can shoot while reloading, such as Benelli M4, SPAS-12 Cobra and UTS-15. Thus, they deal high damage too.
- Beware that the Joker's attack range is quite far so keep a distance.
- If you can't see the joker clearly, just spray the map with a high ammo capacity machine gun. Automatic sniper rifles are also recommended.
- AT4-CS is recommended because its rocket can chase the Joker. However, its damage will decrease over range and the rocket's homing ability is limited.
- See the minimap on top of your screen to help you track the Joker.
- When a player becomes the Joker, listen carefully to his night vision goggle being turned on. This helps you to predict the location of the Joker.
This mode was released on:
- South Korea: the first week of January 2012.
- China/Taiwan/Hong Kong/Japan: the second week of January 2012.
- Singapore/Malaysia: 19 December 2012 alongside Zombie Escape, M95 Christmas Edition and MG3 Christmas Edition.
- Indonesia: 16 January 2013 alongside Zombie Escape and MK48.
- Thailand: 12 September 2013 alongside Bazooka Battle, AK-74U, Lightning AR-2 and M79 Gold Edition.
- This mode is based on a Half-Life 2 modification called The Hidden: Source.
- This mode resembles to a custom mod in Counter-Strike called as Ghost Mod. It is a bomb defuse mode where the Terrorists can only use knife but invisible. This mode is officially released in Counter-Strike Online 2 as Stealth mode.