Neevil's Spectacular Voice-Activated Bomb
These bombs have no fuse or other apparent triggering mechanism. They look like spheres made of iron, with only a single flat surface to keep them from rolling away if placed on even ground. Although these are usually referred to a "Neevil's bombs," Neevil himself denies ever inventing such a weapon. Instead of a fuse, the device detonates when it hears a pre-arranged detonation word. To prevent accidents, the word is not "programmed" into the bomb, but set by the owner just prior to use. The owner places the device where he wants it to be, puts his hand atop the smooth surface, and says "Activate Explosives" followed by the word he wants to invoke detonation. The bomb then arms itself and waits to hear that word. It will wait up to a week before its magic runs out. Once activated, that bomb may not be disarmed, and one must be very careful when moving it, to avoid it being set off. The trigger word must be spoken in the original language used to arm the bomb.