Barrier of Retention
(Abjuration)(Wards)

Range: Special
Components: V, S, M
Duration: 1 turn/level
Casting Time: 1 turn
Area of Effect: 10'-cube/level
Saving Throw: Neg.

 This spell creates a one-way invisible force field around the area of effect. The spell creates one 10' X 10' X 10' cube for every level of the caster. These can be arranged into any rectangular shape the caster desires.
 Intruders entering the protected area suffer no ill effects, but the barrier of retention prevents them from leaving. The spell affects all creatures who fail a saving throw vs . spell . The caster can pass in and out of the barrier freely.
 Intruders trapped by the barrier of retention can cast spells out of the barrier and can use spells such as teleport to escape the protected area. Objects cannot be hurled out of the barrier but can be carried out by an escaping creature. Dispel magic and similar spells negate the barrier.
 The material component is a small cage made of silver wire. The caster must walk around the perimeter of the area of effect when casting.