The point of this build is rather simple, To own early game and bye doing this be able to destroy end game. Your rune setup is for early game as you can see. Ive tried progress vs flat AP runes, and to be honest I will take the flat any day because the difference in the end is pointless once you build your second Arch staff. This is the most possible ability power you can get as soon as possible is the point.
I usually go mid, and start out at level two by going for kills for tormented soil, then rooting them in place with dark binding, and a ignite and youll kill most other mids,or force them to use there summoner skills and be able to finish them off easy with a dark binding and tormented soil shot through the woods next to the tower. Im not going to go insanely indepth into skills and strats because many other guides do that.
I will say though I do not like how archangel staffs are the best AP strat in the game, but I will continue to build this way because it is a good way to win, and not doing the best strat simply because its kind of lame is foolish, besides its fun half shoting a tank after finishing your build