The material below is Open Game Content from a 3PP Source
School abjuration; Level sorcerer/wizard 3
Casting Time 1 standard action
Components V, S, M (a crystalline sphere worth 10 gp)
Duration 1 minute per level (D)
Humans tenaciously protect their homes, and through the years they have perfected magic to aid them in their defense. An immobile, crystalline, weblike globe surrounds you. When the ablative sphere winks into existence, it provides you with improved cover. The barrier does not impede a spell’s line of sight or effect. The sphere is 1 inch thick per caster level, has hardness 5, and 3 hit points per inch of thickness. When an ablative sphere loses hit points, the level of cover it provides is reduced. When the ablative sphere has lost one-third of its hit points, it provides cover instead of improved cover. Once it has lost two-thirds of its hit points, it provides only partial cover. Finally, when the ablative sphere’s hit points reach 0, the globe is destroyed. When an attack reduces an ablative sphere’s hit points to 0, you take any remaining damage.