Oh, you can give it an arc if you want it to be a book and not a short-story collection. Character growth if nothing else, or finding a pattern in the loose magic that has to be contained. But even so it's going to be a looser weave than the quest to kill. At least I hope so, since finding your way too quickly can kill suspension of disbelief, provided it's been set up as a situation where you have to fumble about.
It could be a fix-up, hooking up each story as they go along. Still, that requires the whole thing to be sketched out -- or to be locked into choices that are made while writing the earlier ones, which can be a mistake. (Assuming, of course, that you sell them and have scruples about revising them after. <I>snort</I> If wishes were horses, you would have to pick one to ride. Such a problem.)