I am hoping that this is a "feature" and not a bug, because it makes the Moonblade awesome. But I have a hard time believing this is working as intended.
Taron is a cleric with both the Moon and Darkness domains. The Moon domain gives him access to the Moonblade spell. The Darkness domain gives him access to Shadow Conjuration, Invisibility spell.
While patrolling the Field of the Dead last night, I discovered that attacking with the Moonblade did not break invisibility. The best thing about that is it allowed me to fight undead 1-on-1 and none of the surrounding undead would swarm me because they couldn't see me. However, a lot of the time the undead I was attacking couldn't attack back because it couldn't see me either, so this kind of felt more like an "exploit" than a cool feature.
So, I guess I am looking for confirmation whether this is working as intended or not. And if not, then reporting the bug.