Support
M-Nova is a separate four-tile mahjong game in the RIICHI ORBIT SERIES.
1. How four-tile mahjong works
Start with four tiles, draw one, then complete one three-tile meld plus a matching pair. For example: 2–3–4 dots plus two White Dragons. This is M-Nova’s own two-player rule set, different from standard 13-tile riichi mahjong. Seven-tile matches later in the journey are an extra variation.
2. Play with a friend
The host shares a six-digit invitation number. Confirm your skills, finish preparation and play at the same table. If connectivity is unstable, check your network before deleting the app.
3. Crew and cabin sharing
Open compatible versions of RIICHI ORBIT and M-Nova on the same device to share appearance, accessories, cabin and furniture. Disable sharing in character editing. Lumina, cards, routes and records remain separate; different devices do not synchronize.
4. Saves, reset and ads
Progress is stored on your device. Be careful before deleting the app. Reset requires confirmation in Settings and does not delete RIICHI ORBIT progress. Rewarded videos are optional after regular solo wins. Core matches remain playable if an ad is unavailable.
5. Contact
Email support@doui-lab.com with “M-Nova” in the subject, your app version, device and OS, and steps to reproduce the issue. Do not send passwords, authentication information or images containing private information. M-Nova is currently preparing for release. The game interface is in Japanese.