Alarm, Greater(Spell Compendium, p. 8)
Level: Bard 2, Sorcerer 2, Wizard 2,
Components: V, S, AF,
Duration: 4 hours/level (D)
Uttering a low chant, you ring a crystal bell with the drumming of your fingernails, bringing into being an invisible warded area.
This spell functions like alarm (PH 197), and in addition the spell works on creatures traveling through the area on coterminous or coexistent planes (DMG 150), such the Ethereal Plane and the Plane of Shadow.
Focus: A bell made of carved crystal, worth at least 100 gp.