This fist-sized stone glows faintly and can be used to create a bright burst of radiant light that harms undead creatures.
Consumable: Consumable 200 gp
A glowstone radiates dim light in a 2-square radius.
Power (Radiant, Zone) Consumable (Standard Action)
Use the glowstone to creates a zone of bright illumination in an area burst 2 within 5 squares of you. Any undead creature that is vulnerable to radiant damage that enters or starts its turn within the zone is affected as if it had taken radiant damage. For example, a skeleton that has vulnerable 5 radiant takes 5 radiant damage if it enters or starts its turn in the zone. The zone remains until the end of the encounter or for 5 minutes, whichever comes first. Using this power turns the glowstone to dust.
Published in Adventurer's Vault, page(s) 191.