The trick is to maximize your intelligence score (mine is not, I miss 2 points in the screenshot) and insightful reflexes feat.
To boost the reflexes really high one would have to drop endless faith for unearthly reactions and slot another +6 in the epic completionist 4th slot.
That would put me at 76 reflex, 77 with a store potion.
Could go even 2 points higher (79) but at the cost of less spell power so I will not bother.
Yeah the build is focused on spamming Magic Missile spell, Magic Missile Sla, Wizard active past life, Hellball, Energy burst, Wild Shots.
Then you can trow in the rotation Blade barriers, divine punishment and other stuff depending on the situation.