I read a lot about this topic, more precisely I base myself on what is stated here:
- Does the feat Extraordinary Spell Aim affect the creature's space or the creature? (and other linked discussion)
- What happens when an anti magic field gets close to a polymorphed creature?
but about the Extraordinary Spell Aim + Anti magic field combo, I have not yet clear some points.
In all the following examples Jozan is a 15th level cleric with feat: Persistent Spell + Divine Metamagic applied to Persistent Spell + Extraordinary Spell Aim; and with anti-magic field from which he is excluded
As for the Extraordinary Spell Aim effect space, I agree with KRyan when he says that the PC is excluded from the spell's area, not the square where the PC is.
For example, if Jozan takes Vadania (page 34, Player Handbook) close into a grapple, Mialee can cast a Fireball with the certainty of not doing damage to the druid. The spell has no effect on Vadania but takes Jozan because Jozan is excluded from the anti magical field, and not the square he occupies.
But what else damage Jozan?
Do the magic weapons used against Jozan and out of his anti-magic field have bonuses of some kind for hitting and/or doing damage? If Jozan is the target of an arrow, does he take damage if it is magical (for example if the arrow - and only this - is +1) or is fired by a magic bow (for example if the bow - and only this - is +1)? Does the archer have a bonus to hit roll, or to damage and to hit roll or to damage or to neither of the two?
Do the magic weapons used against Jozan and in of his anti-magic field have bonuses of some kind for hitting and/or doing damage? If Jozan is the target of a Greatsword +1, would the enemy have advantages on his roll to hit or damage or both? If an Assassin attacks Jozan using Wraithstrike does this spell take effect when Jozan is attacked?