Karthus: Obliviously Evil
Karthus is my favorite Champion lore-wise because of the enormous difference between what he thinks he’s doing and what he’s actually doing.
He wants to turn everyone undead because he thinks they’re better off that way. After all, he’s having a fantastic time being undead, why shouldn’t everyone else? Except he (lives) resides on an island chain full of people who are severely suffering as a direct result of being undead.
And yet he somehow fails to notice this. My best guess is that the Mist is somehow messing with his perception the same way it messed with Kalista and Hecarim’s memories. As long as Karthus thinks people benefit from being undead, he’ll keep turning them and making the Mist stronger.
And none of the other Champions seem to view him as malicious. Even the people who don’t like him don’t refer to him as outright evil.
Maokai hates his music and wants to destroy him, but that’s Maokai’s policy toward all undead. Kindred’s got mixed feelings on his music. Yorick only tells him that he plans to end the Isles’ state of undeath.
Even Kalista, who pulls no punches in her taunts, doesn’t accuse him of treachery or deception. She calls him an idiot with no idea what he’s getting into, but doesn’t refer to any actual malice on his part.
The West Altar, like Kalista, veers more toward warning Karthus. It tells him no good will come of his sorcery, which should really be obvious. But to him, it apparently is not.
And there’s something intensely relatable about a guy who genuinely wants to help but is screwing it up royal without even knowing it.
"Look papa I got new pets!" with glittering eyes, he shows his nev victims
"Very well son, go and catch more!"