Right now, it's personal. Laezel wants to take off his head with his own silver sword. Any potential "solutions" should ideally maintain that level of anger. Having him fly off before the characters arrive would deflate his role.
I tend to agree that his actions seem odd.
First, I don't know why he jumps to the conclusion that the party has the weapon. "You were on the ship! You must have the weapon." --um, there were a lot of folks on the ship who don't have the weapon, right?--
Second, why would he fly away instead of immediately taking the weapon? I don't think this question is so easily answered, though. Maybe the weapon is dangerous? Maybe he's trying to get away from it and sacrificing Baretha.
There's just so much we don't know, so it's difficult to say this is right or that is wrong. I'm cautious when it comes to jumping to conclusions and assuming I'm smarter than everyone making the game.
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I'm guessing the weapon is sentient, certainly. I'm also guessing it's the sentience of the weapon that altered the typical nature of the tadpole. In other words, it's why the characters are not like the other true souls.
Furthermore, I'm guessing that the sentience within the artifact is actually the dream person we're seeing, as opposed to a manifestation of the tadpole itself.
