Kim Jung-ju, founder of free-to-play giant Nexon, has died at age 54.

Word of Kim's passing comes from The Korea Times, who was informed of his death by a Nexon spokesperson. He apparently died last month in the United States.

Nexon did not provide a cause of death in its statement to The Korean Times. It did state that Kim "had been receiving treatment for depression, and we are sad that it seemed to have worsened recently."

Kim founded Nexon in 1994 after graduating from Seoul National University. The developer and publisher grew to be a powerhouse in South Korea's game industry on the back of games like MapleStory, and KartRider. Its recent hits have included Mabinogi and Vindictus.

Nexon is now headquartered in Tokyo under parent company NXC Corp., where it went public on the Japanese Stock Market in 2011.

Kim is survived by his wife and two daughters.

If you or a loved one are in emotional distress or are otherwise suffering from depression, you can speak with a certified listener with the National Suicide Prevention Hotline at 1-800-273-8255, or text HELLO to 741741.