My read on the WLW's prophecied killing of Kellhus.
He first throws a Chorae, which misses, but destroys Kellhus's wards.
Then he throws a sword, which Kellhus deflects...except that doing so snaps it (because it was notched), and the broken part plunges into his heart.
Both of these throws are screen by the room's debris, but just happen to fly unimpeded through the tumbling stones, shielded by them from Kellhus's sight.
Obviously, this isn't how it goes down, but that's what I thought he was forseeing.