Privacy Policy

1. Information stored locally

Game settings, owned items, your nickname, and your personal best are saved only in your own browser's localStorage by default. The site operator cannot read this data, and it is removed when you clear your browser's stored data.

2. Global leaderboard (sent to a server)

When a game ends, the following is sent to and stored on a server to register your global ranking:

• Your nickname, score, depth (distance), date, and a random device identifier (deviceId) generated and kept in your browser. The deviceId is an arbitrary value unrelated to your identity, used only to keep a single best score per device.
• Your IP address is used only transiently to prevent spam and abusive submissions (rate limiting) and is not otherwise stored.

Leaderboard data is stored on Upstash (Redis). Daily rankings are kept for 7 days and all-time rankings for 90 days (auto-expiring when idle), retaining only the top entries. No accounts or email addresses are collected.

3. Cookies and advertising

This site shows ads through Google AdSense. Third-party vendors, including Google, use cookies to serve ads based on your prior visits to this and other websites. Google's use of advertising cookies (such as the DART cookie) enables it and its partners to serve personalized ads based on your visit history. You can opt out of personalized advertising at Google Ads Settings (google.com/settings/ads), and you can opt out of third-party vendor cookies at aboutads.info.

4. Contact

For questions about how personal data is handled, please reach out through the Contact page.

5. Effective date

This policy takes effect on July 12, 2026.