For many modern urban residents, the typical harbinger of winter is the smell of "oden" steaming on the convenience store counter.
Traditional oden -- vegetables, fish dumplings and other types of food simmered slowly in a soup -- has not only become the top showcase item for convenience stores during the winter season but also a bellwether of the chains' marketing strength.
FamilyMart Co. fired the opening shot in this year's "Oden War" by having an in-house project team start work on an entirely revamped menu way back in the spring.