Dragonbane
(Abjuration)(Wards)

Range: 10 yards/level
Components: V, S, M
Duration: 1d4 rounds + 1 round/2 levels
Casting Time: 1 round
Area of Effect: 5'-cube/level
Saving Throw: Neg.

 This spell prevents any dragon who fails its saving throw from entering the area of effect. The spell affects a cubic area whose sides equal the caster's level times 5 feet; thus, a 16th-level caster could affect a cube whose sides each equal 80 feet. The dragon can cast spells, blast breath weapon, or hurl missiles (if possible) into the area of effect .
 Dragons within the area of effect when the spell is cast are not affected. If such dragons leave the area of effect, they must succeed a saving throw to reenter the area.
 The material components are the priest's holy symbol and a dragon scale.
 The spell's effectiveness can be greatly increased with the casting of a focus spell.