Entropic Shield

Abjuration
Level: Clr 1, Luck 1
Components: V, S
Casting Time: 1 standard action
Range: Personal
Target: You
Duration: 1 min./level (D)
A magical field appears around you, glowing with a chaotic blast of multicolored hues. This field deflects incoming arrows, rays, and other ranged attacks. Each ranged attack directed at you for which the attacker must make an attack roll (including arrows, magic arrows, Melf’s acid arrow, ray of enfeeblement, and so forth) has a 20% miss chance (similar to the effects of concealment). Other attacks that simply work at a distance, such as a dragon’s breath weapon, are not affected.

Source: Player's Handbook