There is lava in hell, right?
Also as for lava in hell, that's up to who you ask. No one has actually SEEN hell-if it exists, and come back to talk about it. In dantes Inferno where he went to hell he described 9 circles and I believe that the 7th the circle of wrath had boiling water or lava filled with souls. In greek underworld Tartarus I believe it also had lava, or at least fires. The Japanese belief doesn't have lava, nor does Chinese if I recall correctly. But I'm not an expert on the subject. But for the most part many accounts of hell do have lava.
How does he smash the undead if they are at the other side of the port?
I was under the impression they were in the same area, as you didn't specify they attacked a different area of the port.