What Would you Change About Karthus if you Reworked him?
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Karthus is a couple of things; he is the Deathsinger with a ghostly choir, he holds the book of the dead and it's many pages, he's an immortal lich, and a death aficionado.... However, his visuals, gameplay, and kit don't really have much to do with his character, besides being a lich. His whole purpose in the lore is to sing and kill all who hear his voice and add their ghostly wails to his choir of souls, and outside of music videos, I have never heard him once sing, or collect a soul. Now don't get me wrong, his visual overhaul was great.... but that doesn't change the fact that the Deathsinger still doesn't sing.
Now I know there will be people arguing that "Karthus is fine the way he is," and "his simple kit is meant for new players" but I am the kind of person to ask, "what if."
What if Karthus had rhythm to his play style? What if his abilities built off of each other and culminated in a crescendo of ghostly echos? What if Karthus did collect souls? What would a modern music based champion play like? What would a book based ability look like?