@Meddler anything by chance for MPen, Void Staff, and Karthus's W in the future?

With all the talk about Armor Pen/Lethality, I was wondering if something was going to be done with MPen? I know it doesn't have quite as much like Armor pen has I think, so I was just curious.

For Void Staff, I was wondering if you were going to eventually lower it's power in favor of being able to have it build into 2 other items like it's AD counterpart Last Whisper.

Also, out of curiosity, will there be any changes to Karthus's W in terms of the slow, or adding any other debuffs to it? (like Grounded) After the nerf to both it and Rylai's, it's become rather hard to be able to at least stick to an opponent that especially has a bunch of dashes up their sleeve (which consists of pretty much half the roster lol)