Kmst 1.2.239

All that and there was some stuff that we've never seen before in maple. Even though all this happens in a span of probably a few minutes within 5 maps (6 if you count the second starting map) it's still pretty impressive how they were able to do stuff like make npcs disappear so that it makes it look like you're saving him and how when you leave a map and go back to it after you trigger an event, the map changes.

I mean this could be incorporated in so many ways (ie. Masteria)

Actually NPCs changing isn't anything new. Some current NPCs animate after you finish a quest and some NPCs for Cygnus quests disappear completely.