"MapleStory 2"

Again, you're assuming that MS2 means the death of MS1, which it absolutely in no way does. There is no indication that Maple Story would be closed down if Nexon made another project, and the notion alone is ridiculous. Why would the close down such a profitable project for an unsure one? Assuming they stick with the same basic side-scrolling, MS2's success is almost guaranteed, of course, but in no way does that mean MS would be history. Nexon is a company, and it's all about money. Guaranteed success = guaranteed revenue. Nexon loves money. Two sources of income are better than one. MS1 and MS2 will almost assuredly co-exist assuming they are two separate games.