A small QoL buff for Karthus

Karthus ult should do 50%/75%/100% hp tru dmg. Also, if his ult kills a champ, they are permanently deleted from the game. This does not affect another Karthus.

This will help the game become much more healthier because cancers like Irelia and Fizz will be deleted quickly, and soon non-meta picks will rise up for a bit until they too are inevitably deleted.

Pls and ty rito.