Wall of Dispel Magic

(Underdark, DnD 3.5)

Abjuration

Level: ; Bard 4; Cleric 5; Druid 5; Sorcerer/Wizard 5
Components: V, S
Casting Time: 1 standard action
Effect: A plane of dispel magic whose area is up to one 10-ft. square/level
Duration: 1 minute/level
Saving Throw: None
Spell Resistance: No

This spell creates a transparent, permeable barrier.
Anyone passing through it becomes the target of a dispel magic effect.
A summoned creature targeted in this way can be dispelled by the effect.
The wall of dispel magic cannot be seen or felt by ordinary means, or even via a see invisibility spell.
Detect magic indicates the presence of the effect, and true seeing reveals both its presence and its purpose.