Level: Sorcerer 6, Wizard 6
Components: V, S, M$
Casting Time: 1 standard action
Range: Close (25 ft. + 5 ft./2 levels)
Target: One interplanar gate or portal
Saving Throw: None
Spell Resistance: No
You cast a silver bar in the direction of the portal and it vanishes, becoming a semitranslucent net of silver magic that briefly encases the portal before disappearing.
You can permanently seal an interplanar gate or portal. The spell prevents any use of the portal, although seal portal can be dispelled by a dispel magic spell. A knock spell does not function on a sealed portal, but a chime of opening dispels seal portal if seal portal was cast by a spellcaster of lower than 15th level.
Once a portal is opened, seal portal does not remain in effect and must be cast again.
Material Component: A silver bar worth 50 gp.
Source: Spell Compendium, page 181. Previously published in the Planar Handbook, page 104.