The Kitamoto Higashi Chuo Stores and Commerce and industry associations bring you an Halloween costume contest with a top prize worth winning; 2 tickets to a theme park in Uruyasu (Disney I would guess). The runner up prize is equally tantalising; a 10,000 yen voucher for JTB. Contest entry is free, but limited to the 1st one hundred entries.
Apart from the contest there is parade and trick or treating. All takes place just outside the east side of Kitamoto station along the main thoroughfare. It starts at 10am and will finish around 3pm. It sounds like a fun day out for a family.
The phone number for queries about the contest, Japanese only, is 048-593-7576. More information is on a tourist page for Kitamoto, in Japanese: https://www.city.kitamoto.saitama.jp/kanko/oshirase/1433238745160.html