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Counter-Strike Online 2 (CSO2 or CSOL2) is a spin-off MMOFPS in the Counter-Strike series. It is targeted towards the Asian gaming market, developed by South Korean company NEXON Corporation with oversight from license-holder Valve Corporation, and is using the Source engine.
Counter-Strike Online 2 started off as a online game based on Counter-Strike: Source by NEXON Corporation. During its development, some unused concepts for Counter-Strike: Global Offensive are reused in CSO2. For example, the character customation concept appeared in the early stage of the development of the CS:GO, and this feature is absorbed into the Counter-Strike Online 2.
Counter-Strike Online 2's engine has been ported to Source of a newer version in Summer 2017 along with the addition of a new UI, and Counter-Strike Online 2 was released in Japan at that time. However, for its poor operation, all of its servers were forced to shut down in 2018.
The game is implemented with lots of game modes based upon some popular community mods, and Nexon makes them as its official modes with more features.