Board Thread:Lore Discussion/@comment-67.44.208.243-20170601212340/@comment-26213507-20170601223156

I don't recall him saying such a thing. Being the First Dragonborn (if I recall correctly), he is probably older than Harkon, but since Harkon is a vampire (and still alive), I doubt that he "killed" Harkon, only for him to be brought back.

In any case, he should hear that Harkon is alive during the game, and therefore he didn't actually kill him (that is, if what you're saying is true, which would make its inclusion all the more confusing).

However, I'm pretty sure he says no such thing.