As one of the leading Korean online game companies, CJ Internet provides a variety of online games through its game portal called Netmarble. CJ Internet’s FPS(First Person Shooting) game Sudden Attack, which was released in mid 2005, dramatically grew in stature by threatening the no.1 position of Special Force. The game even outpaced Special Force in terms of user number in just 5 months of launching on the back of fervent support of teenage users. Sudden Attack which secured 2 million users as of Oct.2006, 3 times bigger than the number of Special Force users, is now faced with the issue of fee charging. That is because Sudden Attack, which has been provided free of charge for the past 1 year, is lagging far behind Special Force in terms of profitability. At the same time, a string of competitive FPS games such as Counter Strike Online are soon to be released. In particular, the online version of worldly famous Counter Strike is targeting teenagers and female users, core customer base of Sudden Attack. In a nutshell, Sudden Attack is in a very complex situation where it must think hard about how to defend itself against rival games while increasing sales at the same time. Sudden Attack, which successfully implemented offensive strategies against Special Force, can do it again in terms of executing defensive strategies?The core issue of this case is what kind of offensive and defensive strategies a follower must implement in a growth stage industry. Korean online game Sudden Attack’s dramatic experience is an optimal example that raises questions over both issues. In other words, the Sudden Attack example provides insight into two issues, namely, through what market strategy a no.2 player can overcome a no.1 player and make it to the top and how it can defend itself against market competitors after becoming a leader.