Green Dice Inc. (Headquarters: Setagaya-ku, Tokyo; Representative Director: Atsushi Saito, hereinafter "Green Dice"), which operates the experience-based puzzle-solving game brand "Tumbleweed," and Langue de Chat LLC (Headquarters: Shibuya-ku, Tokyo; Representative Member: Hiroaki Hosono, hereinafter "Langue de Chat"), which handles technology development in the puzzle and mystery-solving domain, are pleased to announce that they have entered into a business alliance agreement for the joint development of online puzzle-solving games, effective July 1, 2026.

"Nazotoki Game Online" is a platform for purchasing and managing the online puzzle-solving content offered by Tumbleweed. Users can enjoy authentic puzzle-solving experiences anytime, anywhere, from their smartphones or PCs.

Through this alliance, by combining Tumbleweed's expertise in creating and operating puzzle-solving games with Langue de Chat's strengths in system development, the two companies aim to expand the content lineup of "Nazotoki Game Online" and further grow the service.

Background of the Business Alliance

Since its founding in 2016, Tumbleweed has developed experience-based puzzle-solving events with the theme of "one-time experiences." To date, they have produced and operated over 123 original events (as of June 2026), with cumulative sales of take-home puzzle kits exceeding 250,000 units. Currently, approximately 1,000 customers visit their events weekly.

In August 2022, they launched their official fan club, "Tumbleweed Nazoclub," offering unique online puzzle-solving experiences and exclusive content.

Furthermore, in April 2025, they launched "Nazotoki Game Online," an online service that allows users to easily enjoy puzzle-solving games from their smartphones or PCs, expanding their offerings beyond real-world events.

Meanwhile, Langue de Chat, as a technology development company specializing in the puzzle and mystery-solving domain, has been responsible for the system development and maintenance operations of various online services provided by Tumbleweed, including the development of "Nazoclub" and "Nazotoki Game Online."

Through approximately four years of collaboration, both companies have shared knowledge regarding the design philosophy of puzzle-solving experiences and service operations. Now, they will further develop this relationship by jointly operating "Nazotoki Game Online," aiming to deliver enjoyable online puzzle-solving experiences to a wider audience.

Details of the Business Alliance

The two companies will leverage their respective strengths to jointly promote the online puzzle-solving game business.

Green Dice Inc. (Tumbleweed)

Planning and production of puzzle-solving content

Service operation and promotion

Planning and development of online events

Langue de Chat LLC

Planning and development of service systems

Maintenance, operation, and functional improvements

Research and development of new services and features

About "Nazotoki Game Online"

"Nazotoki Game Online" is an online puzzle-solving service that can be enjoyed anytime, anywhere, from smartphones and PCs.

It offers a diverse range of puzzle-solving experiences, including games that can be played immediately after purchase and online event-style games.

Furthermore, streaming and playthroughs are welcomed, creating new online puzzle-solving experiences where streamers and viewers can challenge games together.

Since its launch, the service has been used by many users. The popular title "ONE OPERATION" has been played by over 4,000 people cumulatively.

Additionally, the latest title "Nazomamire ~Special Edition~," released in June 2026, sold over 2,000 copies in just 10 days, receiving widespread acclaim.

Through this business alliance, the companies aim to strengthen the service infrastructure, develop new features, and expand content offerings to create a platform that more users can enjoy.

Official HP: https://online.tumbleweed.jp/

Future Developments

Moving forward, both companies will focus on:

Expanding online-exclusive puzzle-solving content Developing new online event formats Strengthening collaboration with puzzle-solving creators Implementing online initiatives linked with real-world events

They aim to further develop the online puzzle-solving market through these initiatives.

Comments from Company Representatives

Atsushi Saito, Representative Director, Green Dice Inc.

We are pleased to announce the business alliance with Langue de Chat LLC for the "Nazotoki Game Online" business.

Langue de Chat and we have been collaborating since before the launch of "Nazotoki Game Online." As the demand for online entertainment grows, we believe that by merging the strengths of both companies, we can offer more innovative and high-quality puzzle-solving experiences.

With this alliance, we will strive as one team to create new value in the market and deliver moving experiences to many users.

Hiroaki Hosono, Representative Member, Langue de Chat LLC

As a development partner for "Tumbleweed Nazoclub" and "Nazotoki Game Online," we have nurtured these services with the Tumbleweed team for approximately four years.

From now on, as business partners, we will combine our respective expertise in content and systems to create new puzzle-solving experiences achievable only online, and a platform that will be loved for a long time.

Company Overview

Green Dice Inc.

Location: Green Road Shimokitazawa 2F, 2-16-2 Kitazawa, Setagaya-ku, Tokyo

Representative: Atsushi Saito, Representative Director

Business Activities: Planning and operation of the experience-based puzzle-solving game brand "Tumbleweed."

Details: https://tumbleweed.jp/

Langue de Chat LLC

Location: YAZAWA Bldg. 3F, 3-1-9 Shibuya, Shibuya-ku, Tokyo

Representative: Hiroaki Hosono, Representative Member

Business Activities: Web service development and operation in the puzzle and mystery-solving domain. In addition to system development for entertainment businesses such as "Nazoclub," they operate their own labels LogicPuzzle.App (Japan's largest pencil puzzle submission site "Puzzle Square JP") and EnigmaHouse (including the mystery creation support platform "EnigmaStudio").

Details: https://langue-de-chat.llc

Inquiries Regarding This Matter

Public Relations Department, Green Dice Inc.

E-mail: info@tumbleweedjp.info

FACT BOX

  • Source: PR TIMES
  • Category: 業務Partnership