Privacy Policy
Last updated: October 30, 2026 · Applies to: the Mayhematic game and demo on Steam, and mayhematic.io.
Who we are
Mayhematic is made by Saamis, Finland ("we"). Contact for anything in this policy: support@mayhematic.io. We have not appointed a data protection officer; we are not required to.
The short version
- The game does not ask for your name, email or payment details. Steam handles your account and purchases. The only place we ask for an email address is the optional signup form on mayhematic.io.
- If the game crashes or hits an error, it sends a technical crash report so we can fix the bug. The report carries a random installation ID but no name, account number or IP address. You can turn this off in Settings → Game → Online & Privacy → Crash Reports.
- Online features (leaderboards, multiplayer, achievements) run through Steam and use your Steam account ID.
- We do not sell your data, show ads or build advertising profiles.
What we process, why, and on what basis
| What | Details | Why | Legal basis (GDPR Art. 6) | Your choice |
|---|---|---|---|---|
| Crash and error reports (Sentry) | Error message and stack trace; up to 100 recent log lines ("breadcrumbs"); operating system, CPU, GPU and memory; game version; basic run context (wave number, run id); and a random installation ID created by the crash-reporting library, so we can tell how many players a bug affects. The ID is not derived from your hardware or account; it changes if you reinstall or clear the game's data. Before sending, the game removes Steam account numbers, your Windows user-folder name, your computer's name and your IP address from the report. No screenshots are taken. Reports are sent when an error happens, plus one short notice on the launch after a launch that failed to reach the main menu (so we can find start-up freezes). There are no routine per-launch pings. | Find and fix crashes and bugs | Legitimate interest (6(1)(f)): keeping the game working. We think a player reasonably expects a game to report its own crashes. The reports identify an installation, not a person, and we do not combine the installation ID with any other data. | ON by default. Turn it off in Settings → Game → Online & Privacy → Crash Reports (takes effect on the next launch). |
| Steam leaderboards | Your score and a summary of the run (wave, kills, time, build choices) stored on Valve's leaderboard servers against your Steam account. Other players can see your Steam name, score and run summary. | Run the competitive leaderboards | Legitimate interest / performance of the service you chose to use | Leaderboard scores are submitted when you finish a run. "Hide Leaderboards" in Settings only hides the board on your screen; it does not stop submission. |
| Leaderboard moderation | If a score is impossible or reported as cheating, we may delete it and add that Steam account number to a ban list. The ban list is shipped inside the game files, so anyone can read which account numbers are on it. It contains the account number and the date only. | Keep the leaderboards fair | Legitimate interest (anti-cheat) | Contact us to dispute a ban. |
| Cheat reports you send | The in-game "report" button copies a text summary (board, the reported player's Steam account number, rank, score, run data, game version) to your clipboard and opens our Discord channel. Nothing is sent unless you paste it. | Investigate cheating | Legitimate interest (anti-cheat) | Entirely your choice. |
| Multiplayer | Your Steam account ID and Steam name are shared with the players in your session, and appear in Steam's lobby list when you host a public lobby. Direct-IP play (LAN or dev) shows your IP address to the other player; Steam play does not. Chat messages go to the players in the session and are not stored by us. | Run multiplayer sessions | Performance of the service you chose to use | Play solo, or use a private lobby. Streamer Mode hides names and the host IP on your screen. |
| Achievements, stats, rich presence, Steam Cloud saves | Stored by Valve against your Steam account. Friends can see your current activity ("in lobby", "wave 12") on Steam. | Standard Steam features | Performance of the service | Steam privacy settings |
| Unity engine | Unity's engine may send a one-time anonymous hardware summary (device model, OS, GPU) to Unity Technologies. | Engine statistics | Legitimate interest | None in game |
| This website (mayhematic.io, hosted by Cloudflare) | When you open a page, your browser sends its IP address, browser type and the address of the page. Cloudflare uses this to deliver the page and block attacks. The site sets no cookies and runs no analytics or ad trackers; its fonts, images and video load from mayhematic.io itself. | Show you the site and keep it secure | Legitimate interest (6(1)(f)): running a website at all | – |
| Email updates (the signup form on mayhematic.io) | Your email address, when you signed up and confirmed, and whether you open our emails or click a link in them. Signup is double opt-in: your address is not on the list until you confirm from the email we send. The list is kept by Kit, Inc. on our behalf. | Tell you when the free demo is out, and about festival dates | Consent (6(1)(a)) | Only if you sign up. Every email has an unsubscribe link, and unsubscribing withdraws your consent. |
| Support email | Whatever you send to support@mayhematic.io | Answer you | Legitimate interest | – |
We do not use your data for automated decisions that have legal or similarly significant effects.
Who receives data
- Functional Software, Inc. (Sentry): crash reports, processed on our behalf under a data processing agreement, stored in Sentry's EU region (Frankfurt, Germany).
- Valve Corporation (Steam): leaderboards, achievements, lobbies, cloud saves. Valve is a separate controller for your Steam account; see Valve's privacy policy.
- Discord Inc.: only what you choose to paste into our Discord server. Discord is a separate controller; see Discord's privacy policy.
- Unity Technologies: the engine hardware summary described above.
- Cloudflare, Inc.: hosts mayhematic.io and processes website requests on our behalf under its data processing addendum.
- Kit, Inc. (Kit): the email signup list, processed on our behalf under its data processing addendum and stored in the USA.
- Other players: as described under Multiplayer and Leaderboards.
Transfers outside the EU/EEA
Valve (USA), Discord (USA), Cloudflare (USA) and Kit (USA) state that they participate in the EU-U.S. Data Privacy Framework; Kit's data processing addendum also includes the EU Standard Contractual Clauses. Sentry's parent company is in the USA and also states Data Privacy Framework participation; our crash data is stored in its EU region.
How long we keep it
- Crash reports: 30 days, then deleted automatically.
- Leaderboard entries: while the leaderboard exists, or until we remove a cheating entry. Leaderboards may be reset between major versions.
- Ban list: until the ban is lifted.
- Cheat reports in Discord: until the report is resolved, then deleted.
- Support emails: up to 1 year after the conversation ends.
- Email signup list: until you unsubscribe or ask us to delete your address.
Your rights
You can ask us for access to, correction of or deletion of your data, ask us to restrict processing, and object to processing based on legitimate interest (including crash reporting, which you can also simply switch off). Email support@mayhematic.io. Because we do not know who you are beyond a Steam account number, we may need that number to find your data. Leaderboard and account data held by Valve is also managed through Steam.
You can complain to the Finnish supervisory authority: Office of the Data Protection Ombudsman (Tietosuojavaltuutetun toimisto), P.O. Box 800, 00531 Helsinki, Finland · tietosuoja@om.fi · +358 29 566 6700 · tietosuoja.fi. You can also complain to the authority in your own EU country.
Is providing data required?
No account data is needed to play solo. Crash reports are optional. Steam features need your Steam account, as with every Steam game.
Children
The game is not directed at children under 13 and we do not knowingly collect data about them beyond what Steam provides.
Changes
We will update this page and the date above when the game's data handling changes.
mayhematic.io · Press kit · support@mayhematic.io · © 2026 Saamis