Originally Posted by AskKarthus
My question is what was your guy's reasoning behind this. I like the Shadow Isles connection, but his origin feels off to me. Granted, it is an upgrade from being transformed by marsh goo into a lich of terrible power, but he never seemed that morbid to me.
Riot decided to roll out a bunch of Shadow Isles stuff and were looking for whatever they could connect to it. Hey, Karthus is pretty evil-looking, let's include him in the Shadow Isles! This means he needs a new backstory, so let's make him some guy who likes death. BRILLIANT!
There was no reasoning, it was just Riot being retarded with the lore, like they have been for ages.