Questioner
You've mentioned before that Odium is scared of Harmony. Is it only because of the raw power of the two Shards? Or is he scared of what Harmony represents? (Meaning the possibility of merging two Shards.) Was he aware that this was possible?
Brandon Sanderson
He, on one level, was aware. But it was more of awareness of this as a possibility. It actually happening is part of what has him scared. It's the idea of the two merging Shards both being more powerful and finding a harmony. (Which Sazed is actually having way more trouble doing than Odium realizes.) Those two things really have Odium scared. Because, partially, this means he has to find a way to destroy or split Harmony without taking up a second Shard himself, because Odium knows if he takes up a second Shard, terrible things will happen. And so he doesn't want to do that. (Terrible things as he views them.) And so he's gotta find a way to split this apart, or somehow otherwise defeat.
Now, the more he learns about Sazed's actual state, the less afraid he'll probably be. But that's an advantage that Sazed has right now.