Izaya Orihara uses this shogi board to plan and observe the actions of himself and others in Ikebukuro, arranging pieces from various board games in a way that only he and apparently Shingen Kishitani can understand. Every piece represents a person who has caught his interest or who has an important role to play in his plans, and he changes their position on the board depending on what they do. The identities behind most of the pieces are never revealed.
In the beginning of the Yellow Scarves Arc Izaya lights the board on fire, imagining the same fate for Ikebukuro as his plans are realized. He has obtained another board by the end of the arc.