Interesting guide, but I do think that getting a void staff so early isn't that effective. I'm just assuming around mid game you'll get your void staff, and at that stage most champions won't have any magic resistance items. With the base 30 magic resistance, your runes and sorcerer's shoes will penetrate about 28 of their magic resistance, meaning your void staff will only penetrate about 0.8 magic resistance of the 2 magic resistance due to the 40% the void staff gives you (not taking the 15% spell penetration from archaic knowledge into account). You'd be much better off with a abyssal scepter or haunting guise, so it brings your enemies' magic resistance to 0.

looks simple and effective. I'll try this out.