I'm not sure what you mean. The physics model they have here is pretty decent. You can, for instance, smash a stone pillar(preferable by throwing an enemy into it, but I haven't quite pulled it off yet), then pick up some of the pieces and slam or throw them into enemies. Sure it's not like Far Cry's physics engine(pushing a barrel down a cliff, causing it to roll into and kill enemies), or anywhere near what the now MGS game is supposed to be capable of(slicing a watermelon, or your enemies, into different-sized pieces), but for a free(2play), it's pretty good. It reminded me a bit of Devil May Cry's fighting a bit, only it doesn't have something like running along a wall, stabbing an enemy in the head with one sword, and using that enemy to perform a wide circular cut on several others with the other sword. That might be a little too badass, though.
You're right to think Maplestory when you think of Nexon. It's the only when they themselves devoloped for sure(probably also PopTag, but that's MS related I think). Not sure about Dungeon Fighter or Combat Arms(which was made using a 3rd party engine), but Mabinogi was developed by devCat, as was Vindictus.