The Locate City Bomb.

Speak aloud the pass code, either in or out of character while in possession of the item and it activates, code is same for all games, so metagaming the code is possible and not at all discouraged. Once activated the Locate City Spell is cast as per the original interpretation.
The die rolled is specially bought for the purpose of rolling the Reflex save for every single creature within the radius of the Spell, including PCs. Only the user of the LCB is exempt from the effects.