Cast Bo, Cast bos and run to the stairs. Don't stop, just run.
I get there, cast SW south (illuminates first marker) and cast my venom. When I get near Nih, I either use fade (if swarmed by a skeleton pack and / or vipers) or just lay DS and kick the spawns. Cast more DS and collect a key.
Takes ~ a minute to a minute and a half. To keep from being temp'd, I'd then run countess.
I h8 summoner and his mana ghosts ><