Counter-Strike Online is a Counter-Strike game targeted towards Asia's gaming market released in 2008. It is based on Counter-Strike and was developed by Nexon Co. Ltd. with oversight from license-holder Valve Corporation. It uses a micropayment model that is managed by a custom version of the Steam back-end.
The game also features a variety of additions over the international Counter-Strike, such as the introduction of female characters, numerous new weapons and skins for previous weapons. Most of the weapons are "locked" by default, so virtual cash or in-game points are essential to purchase them. Most special weapons, skins, power-ups, etc. can be purchased with cash points. A variety of other special items can also be bought with in-game points as well.
Counter-Strike Online itself is free to play, but some weapons are bought using points purchased with real money. These weapons usually expire after a certain amount of time but sometimes can be purchased permanently during a promotion. Certain weapons and items can be purchased with points that are gained by getting kills, completing objectives, etc.
Counter-Strike Online includes classic Counter-Strike modes and added more. They are categorized as six: Classic, Deathmatches, Zombie Infection, Scenarios, Fun and Others.
- Classic: Round-based match. The modes available are Bomb Defuse, Hostage Rescue, Assassination and Basic.
- Deathmatches: Players will respawn immediately after death. The modes available are Deathmatch, Team Deathmatch and Gun Deathmatch.
- Zombie Infection: Humans must survive incoming zombie attacks. The modes available are Zombie 1: Original, Zombie 2: Mutant, Zombie 3: Hero and Zombie 4: Darkness.
- Scenarios: A group of 10 players must survive and annihilate computer-controlled enemies to clear specific goals. Some maps have to defeat a boss. Modes available are Zombie Scenario and Human Scenario.
- Fun: Spin-off modes that are fun to play. Modes available are Hidden, Bazooka Battle, Soccer, Challenge and Item Battle.
- PvPvE: Player vs Player vs Environment modes that are Zombie Union, Metal Arena, Battle Rush, Zombie Shelter and Beast.
On April 5, 2012, Nexon and Valve announced a partnership to develop Counter-Strike Online 2, which is to be based on an enhanced Source engine, and will offer enhanced graphics, powerful impact physics, and more new features. It has been confirmed that Counter-Strike Online 2 uses the same Source version as Counter-Strike: Source. However, it is not a copy of CS:S since all the features in game like models, maps and sounds are completely rebuilt by Nexon of South Korea.
Professional leagues and tournaments
Counter-Strike Online is one of the largest esports, with various annual tournaments taking place worldwide.
The World Cyber Games 2012 Grand Finals in Kunshan hosted a Counter-Strike Online tournament, at which teams from China, Taiwan, Malaysia and South Korea competed. The TYLOO team from China won the tournament.
Counter-Strike Nexon: Zombies was released on Steam the October 7, 2014. This is the first adaptation of Counter-Strike Online to be published via Valve Corporation's Steam content delivery system. Counter-Strike Online Singapore/Malaysia, which also run in English language, was closed six months later.
- "Tiancheng agent confirmed century epic FPS-class online games giant for "Counter-Strike Online"".
- "Trai nghiem Counter-Strike Online-Game moi ra mat tai Viet Nam".
- "Q&A: Valve Explains Why PC Gaming's Gaining Steam". Gamasutra. 2008-03-06. Retrieved 2008-03-06.
- Mallory, Jordan (2012-04-06). "Nexon, Valve announce Counter-Strike Online 2 for Asian territories". Joystiq. Retrieved 2013-04-01.
-  on wcg.com, accessed on October 17, 2012
- Cheben, Mark (2007-07-27). "Leading International Studios Join Forces to Extend the World's #1 First Person Multiplayer Game". GotFrag. Retrieved 2007-10-12.
- "Game Watch (Translated)". (This game is not suitable for children under the ages of 13. Contains graphic violence.)
- "Nexon Finding ways to expand cso business in Indonesia, India & other area.(8-1-2012)". (CSO is available in Indonesia & coming soon in India till end of 2011. [Possibility of Launch Canceled])
- "trai nghiem Counter-Strike Online:su that vong da duoc tien lieu".
- (Korean) Official site of South Korea