I feel so bad for the poor tavern's owner. You people sure do love your collateral damage, don't you? Speaking of, how come the place isn't on fire from when Ben breathed a fire jew all over the place?
Let me explain this as Rockvale has been created. And no... it is not magic. Just science my dears.
Rockvale is made from wood from shipwrecks. Wood. Wood absorbs water over time and being close enough to a set of cliffs and rocks, plenty of water splashes up. Plus, the rain soaks a lot of the wood and thus rots the wood over time which allows even more water to soak in making some of the wood wet and will let out liquid when enough pressure is applied. The slums have it bad on this front and thus has more water soaked buildings which smell of rot. Thus, to end my tirade here, the ambient water in the wood would have to be removed in order for the fire to catch on. So, they are just lucky they chose to build wood buildings by a very active portion of the coast with a sort of jungle not too far away.
Now then, to writing the finish of this massive fight.