Shibuya is divided into several districts, some of which may be inaccessible on certain days or blocked by a wall that can only be removed by satisfying the request of a nearby Reaper, such as erasing Noise symbols, putting on a certain brand of clothing, or bringing an item. Neku can scan the area by activating a special pin. This scan reveals the thoughts of the non-player characters in the Realground and memes, which may help to progress the plot. The scan also reveals random Noise symbols that drift about the area, or in some cases, float around a specific character. The player initiates a battle by touching Noise symbols; each symbol constitutes one round of battle. Selecting more than one Noise symbol at a time results in a multi-round battle (referred to in-game as multiple noise "reductions") that gradually increases in difficulty with each round, but conversely leads to greater rewards upon success. Altering the difficulty of the Noise and the amount of health for Neku and his partner also alter the benefits conferred.