Spell Wall

Regular; Resists spells cast through it 
Creates a wall of anti-magic. The wall resists any spell cast through it from  one side, specified by the caster upon casting Spell Wall. It also acts as a Scrywall.

Exception: It does not affect Missile spells at all, including Thrown spells.

If the Spell Wall fails to resist a spell cast through it, the spell breaks through, but the wall still stands, its Endurance (p. 10) weakened by 1. 
Upon reaching Endurance 0, the wall dissipates. Spells passing through the wall from the “safe” direction (usually the side that the caster stands on!) are not resisted or affected in any way. 
The wall is cast in one-yard increments, either all at once or piece by piece. When adding new segments to a weakened Spell Wall, the new segments assume the Endurance of the “weakest link.” The only way to “repair” a weakened Wall is to cast it anew. 
The Spell Wall is four yards high, so it is possible to cast across it from a high enough elevation. Higher walls can be created by spending proportionately more energy (double energy for double height, and so on).

Duration: 1 minute. 
Cost: 2 per one-yard piece of Wall to cast. Same cost to maintain. The Spell Wall may also be cast horizontally, as a “ceiling” or “floor”; each point of energy will then cover two hexes on a battle map. 
Prerequisite: Spell Shield.

Item 
A Spell Wall may be made permanent for 100 times casting cost. Mages often cover windows or skylights in this fashion. “Permanent” Spell Walls do not weaken when penetrated.