Khelben's warding whip

Khelben's warding whip was an arcane abjuration spell that directly countered movable magical force spells, particularly the various Bigby's hand spells.

Effects
The spell created a whip of magical force that had a range of 10 yd (9.1 m) centered on the caster. Khelben's warding whip lasted for one minute per the caster's level and while it was in effect it could be directed to attack or parry at will, but the caster could not use other weapons or cast other spells. This spell granted the caster complete immunity to the push spell and it destroyed or dissipated low-level force spells, such as battering gauntlet, fantastic fencers, shield, strangling grip, and Tenser's floating disk on contact. Bigby's interposing hand was also destroyed on contact but at a possible risk of the whip being destroyed. As the strength of the Bigby's hand spell increased, the chance of the hand being destroyed decreased while the chance of the whip being destroyed increased.

Khelben's warding whip was ineffective against stationary force field effects such as wall of force and prismatic sphere. It could do no harm to living beings but could be used to parry attacks as long as the caster got to react first. Any successful parry did no damage, but was effective against even magical weapons including those summoned by decastave, spiritual hammer, etc.

Components
In addition to verbal and somatic components, this spell required a segment of drawn wire and a pinch of electrum powder to cast.

History
This spell was very specialized and rare in the Realms. As the name implies, it was developed by Khelben Arunsun and was eventually published in "Volo's Guide to All Things Magical" where it became generally known to the magical community.

Rumors and Legends
This spell was apparently invented specifically in response to the various Bigby's hand spells that made their way into the Realms at some point in history. It is likely that Khelben and Bigby met at least once and the meeting was somewhat less than cordial. Khelben's apprentice Illistar was the recipient of this observation by Khelben about Bigby: "The old goat comes up with one good gimmick, and beats it to death with a rock."