So I've been thinking why you'd ever knowingly play Air Wizard versus Necromancer because one of your best spells is Poison Gas Cloud. However, even wasting 8 spell points on them, you still have enough tricks to beat a Necromancer. Your greatest weapon is Incorporeal (better than Resilient) and a Necromancer is not frontline for a Mage Staff so the worst is Gray Wraith, the latter comparing unfavourably to your Whirling Spirits.
The Whirling Spirit is amazingly good, wall-bashing or pushing the opponent into Oozes (with Poison Gas Cloud above it if against living). And the amazing board control against lumbering Zombie Brutes (the danger), forever battering them back from you. As with Earth mage, going Nonliving negates Bloodthirsty and Poisons. So despite the useless Poison Gas Clouds (retained so that book works even better against other mages as they will only hinder), the build below (plays like an Earth mage) should be a solution to beating a Necromancer.
Don't be embarrassed to Teleport the enemy mage into a zone full of Oozes and push him back in with Whirling Spirits.
Air Wizard Control
Equipment (14)
1 Arcane Ring (1)
1 Suppression Cloak (2)
1 Elemental Cloak (1)
1 Dragonscale Hauberk (2)
1 Leather Gloves (1)
1 Leather Boots (1)
1 Mage Wand (2)
1 Elemental Wand (2)
1 Veteran's Belt (2)
Conjurations (33)
1 Battle Forge (4)
2 Mana Crystal (2)
1 Mana Siphon (3)
1 Suppression Orb (4)
1 Wizard's Tower (2)
1 Deathlock (4)
1 Idol of Pestilence (4)
1 Mordok's Obelisk (2)
4 Poison Gas Cloud [8]
Creatures (28)
4 Devouring Jelly (12)
4 Whirling Spirit (16)
Enchantments (9)
3 Harmonize (3)
1 Rhino Hide (2)
4 Nullify (4)
Incantations (26)
4 Dispel (4)
4 Dissolve [8]
2 Seeking Dispel (2)
4 Teleport [8]
1 Force Wave (2)
1 Purify (2)
Attacks (10)
2 Jet Stream (2) - wand
1 Lightning Bolt (2)
1 Fireball (4)
1 Surging Wave (2)
