If you've spent any amount of time in Korea or even hearing about Korea you will know that Koreans are obsessed with Starcraft. I was not surprised then when I went hunting for Korean RTS games that were not Starcraft, I came up mostly dry. By mostly I mean that I found no current Korean made RTS games. I haven't completely given up the search, and I did find some, just not playable at this time. I'll detail a couple of them here.
The first is TKOnline. The TK stands for Turbulent Kingdom. TK was an active RTS that apparently started to undergo a redesign last October. News on the site is scarce, and there haven't been any updates. There are users occasionally posting on the site asking about updates, but so far the devs have said nothing. If it makes a come back you can be sure I'll write about it. The art style is a little cartoonish and reminds me vaguely of Warcraft 3. It is an independent website and not part of a portal. The company behind it is Mobicle who seems to be mostly focused on a few mobile games. This is their only PC game that I can find.
The other game I've found is a game called 3rdplanet. This RTS game doesn't appear to have been released yet and I can't find an announced release date. The graphics do look nice and it appears to be a sci-fi RTS with some giant robots. There is also some kind of card game mechanic, but I'm not sure what that is. The company behind the game is UTPlus. They have one other game listed on their website called M Project, but there doesn't seem to be any other info on it. Also with a name like M Project, it is a little hard to search.
Personally I find 3rdplanet to be a little more interesting than TKOnline, but I plan to try them both, if and when they're released. None of the game portals I've joined have any RTS games on them and it appears very few companies want to try and compete with the juggernaut that is Starcraft. With Starcraft II coming out it will probably make the RTS market in Korea even tougher to break.
Update: TK online has finally been released. So for those interested, see my latest post on it here. The 3rdplanet site is returning a database error, so that doesn't look so good.