I love me a good challenge to try out. The game has some good options, but I believe we can do with some more! I present to you the pacifist challenge. In this challenge, you must make it to max level without killing a single being or you fail, like with a hardcore character. It would be a nice way to see people build and focus on other forms of experience, such as discovering areas and leveling professions. It would be a test of their gaming knowledge as to what quests require killing, and what areas are safe to farm. Abilities would be built moreso on defense, travel, and survivability rather than killing. Not sure what rewards would come out of it, but it would certainly be a different and difficult challenge.