User blog comment:Ornsteinthedarkhorse/Four Knights of Gwyn/@comment-25730298-20141125153743/@comment-16047389-20141125191551

Sure, but that's not much to support the theory, as they would work well to fight anything, not just dragons. Only Ornstein and Gough have anything evidence that they've fought dragons. Nothing about Artorias's or Ciaran's currently known lore suggest that they have ever fought dragons, and the description of Ciaran's equipment even suggests that she wasn't the first Lord's Blade, and may have not even been a part of the war at all.