NCsoft Corp., a South Korean online game developer, said Wednesday that its second-quarter net profit jumped 67.2 percent from a year earlier on steady sales of its best-selling game. Net income came to 41.4 billion won (US$38.6 million) in the April-June period, compared with 24.7 billion won a year ago, the company said in a regulatory filing. Sales slipped 0.88 percent on-year to 166.8 billion won over the cited period but operating profit rose 47.2 percent to 43.5 billion won. NCsoft said the strong second-quarter bottom line is attributable to sales of its popular role-playing online game Lineage, which posted a record 66.3 billion won in sales in the three-month span. Sales of other online games such as Lineage 2 and Aion decreased due to seasonal sluggish demand, said NCsoft. In the first half of the year, sales dropped 4.8 percent on-year to 322.3 billion won and net profit slumped 5.1 percent to 75.8 billion won, the company said. Shares of NCSoft rose 4.28 percent to 329,000 won on the Seoul bourse as of 10:55 a.m.