How will Szeth use the sword? If I remember correctly, Nightblood sucks the breath of the one holding it.
And Szeth acquired the ability to drew in stormlight through his previous shard right? Will he still retain that ability? If so, then there's a possibility that a storm light can be used as breaths. And if not, then Nightblood will surely kill him. Well, we know that Szeth is not really "evil", but more like a deranged person. He's raised that way, so he thinks differently from "normal" beings. Any thoughts?