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Gate Seal

(Forgotten Realms Campaign Setting)

Level: Bard 6, Cleric 6, Druid 6, Sorcerer 6, Wizard 6,
Components: V, S, M,
Casting Time: 1 action
Range: Close (25 ft. + 5 ft./2 levels)
Target: One gate or portal
Duration: Permanent
Saving Throw: None
Spell Resistance: No

You permanently seal a gate or portal.
Gate seal prevents any activation of the gate or portal, though the seal may be negated by a successful dispel magic cast upon the spell.
A knock spell does not function on the gate seal, but a chime of opening dispels the spell.
Material Component: A silver bar worth 50 gp.