Not bad
It's 3rd game from a company that has been using the same engine for about 7 years. The game engine hasn't changed much. So, don't expect nice grahpic, but it does look cute.
The game provides a certain degree of freedom but leveling characters can get somewhat annoying. It's real time action RPG. You fight without turns.
So, basically, if you hit fast and don't give time for monsters to attack back, you are a winner.
You are going to need more than basic knowledge in Korean in order to finish this game as getting information from NPCs are very important and they don't often tell you directly. So, knowing Korean well is a must.