Hey Riot, people want Magic Pen removed, let us do it to Armor Pen too then.
I know it is like an eye for an eye, and it can make the whole world blind. But here is the thing, here are all the magic items with Magic Pen:

Here are all the AD items with Armor Pen or items that work like Armor Pen:

There is a vast selection of Armor Pen items Vs Magic Pen items. Are we really going to have this dumb discussion, when we know you are a moron and wrong?
Also, do not come with this stupid, "but there is more armor than magic resists items" bullshit.
Armor:

Mix:

Magic:

There is plenty of armor and magic resist items. Some of the magic resists items gives damage for either ill. People bitching like Magic Pen is the most broken thing in the world when they have limited options. Get real people.
have zero pen
in that it requires stacking, it's an item hand tailored to champions who are required to stack HP, AD, and CDR, most of whom also stack a good chunk of Armor and Magic resist so they wind up not actually dealing much damage in exchange for not getting popped in a quarter second
in relation to the slot they hold.
mages only have to build 2 slots worth of pen to effectively deal true damage to most enemy champions, everyone else builds 3, with the exception of bruisers who build only 1 but deal less burst damage and more sustained damge.
it does nothing,