The character brings into being a mobile, hemispherical energy
field that prevents the entrance of most sorts of living
creatures. The effect hedges out animals, aberrations, beasts,
magical beasts, dragons, fey, giants, humanoids, monstrous
humanoids, oozes, plants, shapechangers, and vermin, but not
constructs, elementals, outsiders, or undead.
Note: This spell may be used only defensively, not
aggressively; forcing an abjuration barrier against creatures
whom the spell keeps at bay collapses the barrier.