It is a decent AP/Survivability build, but I think it works too hard on Health instead of mana. You could go in there and think you would last long in a team fight, but after afew rift walks and three spells you would have to go back for mana. Exhaust is Kinda useless due to Force Pulse giving you the slow, and Ignite is fine, yet could be substituted for something better

Yo man.. here this is just for you

"Will of the Ancients will now grant double bonus to the holders if multiple members of a team have the item, like all other aura items"

http://www.leagueoflegends.com/board/showthread.php?t=148864 enjoy... have ****ing fun dude.

nice build