was a fantasy-based massive multiplayer online role-playing game (MMORPG) produced by Webzen, a Korean-based company.

The game was launched in Taiwan on April 19, and in China on May 24, 2007 as a paid online service[1] and closed on July 3, 2013.

The hunting maps were for tracking down monsters to level up characters, gather items and acquire in-game money.

The game underwent four stages of beta from September 2005 to May 2006 in South Korea, and received high marks from gamers.

[9] NHN USA Corp., the publisher of SUN in North America made a license agreement with Webzen in May 2009.

Players had to talk with a specific non-player character (NPC) in each town to create such rooms.

[citation needed] Like in Webzen's earlier MMORPG, MU Online, players had a selection of five different character classes: Dragon Knight, Berserker, Valkyrie, Elementalist and Shadow.

For example, a Dragon Knight could be a Valkyrie, and an Elementalist had the possibility of being a Shadow; all of this is in terms of skill set and play-style.