Karthus' old lore.
The vast quantities of physical magic that were consumed and destroyed during Valoran’s numerous Rune Wars have scarred much of Valoran. Many locations far from civilization have been morphed into hazardous and dangerous locales. The Howling Marsh is one of these places, and the self-appointed overlord of this land is the lich known as Karthus. It is thought that Karthus was a mage who, in life, was foolish enough to enter the fetid waters seeking his fortune, and that he was forever transformed by whatever dark magic permeates the swamp. Karthus now rules over his swampy dominion with an iron (albeit skeletal) fist. Visitors are not welcome, and those who are not scared away by the lich’s terrible power most likely end up as one of the undead themselves… skeletons and zombies in Karthus’ growing army of eternal servants. On the darkest of nights, Karthus is said to sing the tales of those who have succumbed to the swamp, past and present.
Karthus’ tenure in the League of Legends is one of the more unusual ones in the history of the League. First, it is highly unusual that a lich who was known for isolation and hatred of life would even be a willing part of an organization which promoted the preservation of life. Next, Karthus specifically eschews the accrual of power and influence gained through service to the League; he is essentially an unpaid volunteer. This behavior is completely different than what his life outside of the League would have onlookers believe. Karthus has never spoken about his intentions in being a champion of the League, and in fact becomes quite agitated when asked about it. In the interests of not aggravating a lich, most sensible people subsequently drop the issue.
‘’Come visit my home, and I shall sing a dirge of your life as it once was.’’