In the Dragonblight quest, “On Ruby Wings”, after the player uses the dragon to kill the giant he is riding, Grand Necrolord Antiok has a tendency to shoot back up into the air to the height he was at while on the giant, placing him completely out of reach for melee classes. The only way I could bring him down on my most recent attempt was to suicide to reset him, long corpse run, rez, then resummon my dragon and kill the giant again.