Evocation, sponsored magic with thematic bonuses, lawbreaker 2, refinement 1 OR evocation, sponsored magic, refinement 3 OR evocation, thaumaturgy, the sight, refinement 1, Item of Power Staff that is equivalent to 3 refinements.
* The first gives you get Power 10/Control 11 for offense with the sponsored magic theme you are using (usually Kemmlerian Necromancy or Outsider Magic) by supercharging to stack bonuses, Power 8/Control 9 for non-offense. (you are using a +2 control/power offense focus, the rest from specialization, sponsored magic and lawbreaker bonuses)
* The second gives you Power 11/Control 11 for your theme/element in offense, Power 7/Control 8 in non-offense. It has a slight offense advantage, a slight defense disadvantage but no Lawbreakers. (you are using +4 offense control focus and +3 offense power focus, the rest from specialization and sponsored magic bonuses)
* The third is basically a wizard that has a +5/+1 power offense focus as an IoP, gets a +4 control offense focus from his slots, has +1 control / +2 power in specializations, and thus Evokes for his element at Power 11/ Control 11 for offense, Power 6 / Control 7 for the rest.
There are, potentially, even stronger builds if you combine evocation, sponsored magic and an item of power but that's pushing the limits of the GM's patience.