Homunculus Shield
(Evocation, Necromancy)

Range: 0
Components: V, S, M
Duration: 1 round/level
Casting Time: 3
Area of Effect: The caster
Saving Throw: None

 By creating a homunculus shield, the wizard separates a portion of his mind in the form of an exteriorized magical homunculus. This creature is invisible to all but the caster and appears as a miniature version of the caster perched atop the wizard's head.
 The wizard may move and act normally while this spell is in effect. The magical homunculus operates as an independent spellcaster. It may cast only teleport, contingency, and protective spells of 4th level and lower. It casts only spells from the wizard's memorized store of spells, but any spells cast by the homunculus are done so with a casting time of 1. The wizard selects which spells are cast by his homunculus; after they are cast, they are wiped from the caster's memory.
 The homunculus has 1 hit point per two levels of the caster. These points are "borrowed" from the caster; while the homunculus is present, the wizard's hit points are reduced by this amount.
 The homunculus cannot be struck by melee or missile weapons separately from the wizard. It can be damaged separately from the wizard (e.g., by a magic missile targeted at the homunculus or by area effect spells). The homunculus has the attributes and saving throws of the wizard.
 At the end of the spell's duration, the homunculus disappears and any hit points it had are restored to the wizard. Hit points lost by the homunculus can be regained only by magical healing. 
 If the wizard's hit points are reduced to zero at any time during the spell, the wizard is dead even if the homunculus had hit points remaining.
 A wizard with an active homunculus shield suffers a -4 saving throw penalty against magic jar spells cast upon him due to the division of his mental energy.
 The material component is a miniature sculpted bust of the spellcaster.