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Bridge of Sound

(Savage Species)

Conjuration (Creation) [Sonic]
Level: Bard 2, Cleric 3, Sorcerer 3, Wizard 3,
Components: V, S, DF,
Casting Time: 1 action
Range: Close (25 ft. + 5 ft./2 levels)
Effect: One bridge of sound 5 ft. wide, 1 in. thick, and up to 10 ft./level long
Duration: Concentration plus 1 round/level
Saving Throw: None
Spell Resistance: Yes

You create a ribbonlike, weightless, unbreakable, invisible bridge of sound.
The bridge must be anchored to solid objects at both ends, but otherwise can be at any angle.
Like a wall of force, it must be continuous and unbroken when formed.
It is typically used to cross a chasm or a hazardous space.
Creatures can move on the bridge of sound without penalty, since it is no more slippery than a typical dungeon floor.
It is only a physical barrier to solid objects and has no effect on spells, line of sight, gaze attacks, ethereal creatures, or incorporeal creatures and objects.
The bridge of sound can support a maximum of 200 pounds per caster level.
Creatures that cause the total weight on the bridge of sound to exceed this limit sink through the bridge as if it weren't there.
A bridge of sound is temporarily negated within the area of a silence spell, causing anything on it to fall.
If the silence effect ends or is dispelled before the bridge's duration expires, the bridge is once again whole.