Privacy Policy

Crucible Cards ("we", "us") is a free fan project that lets people play trading card games online with friends. This policy explains what data we handle and why. We try to collect as little as possible.

Who runs Crucible Cards

Crucible Cards is operated by its hobbyist maintainers (George and Lewis), based in the United Kingdom. It is an unofficial, fan-made simulator and is not affiliated with, endorsed, or sponsored by any card-game publisher. You can reach us at blissettgeorge@gmail.com or via our Discord.

What we collect

• Anonymous account identifier. When you open the app we create an anonymous account via Firebase Authentication (Google). This is a random ID — it does not require your name or email.
• Optional sign-in. If you choose to sign in (e.g. with Google), we receive a basic profile — a display name and account identifier — so your decks and identity persist across devices. We do not receive your Google password.
• Display name. A name you choose to show other players. Please don't use your full real name if you'd rather not be identifiable.
• Gameplay & lobby data. While you play, your public game state (life total, board, lobby membership, presence, cursor, chat/soundboard, friends and recent players) is stored temporarily in our realtime database so other players in your game can see it.
• Decks & settings. Decks you build and your preferences are stored in your browser (localStorage) and, if you sign in, may be associated with your account.

We do not collect payment information, and we do not knowingly collect sensitive personal data.

How we use it

Solely to run the game: to create lobbies, sync the board between players, show presence and friends, and remember your decks and settings. We do not sell your data or use it for advertising.

Who we share it with

• Other players in the same lobby see your public game state and display name.
• Google Firebase provides our authentication, database, and hosting. Data is processed on Google's infrastructure under their terms. See Google's privacy policy for details.
• Scryfall provides card data and images; loading card images involves requests to Scryfall.

We do not share your data with any other third parties.

Where data is stored

Our realtime database is hosted in Google's europe-west1 (EU) region. Some processing may occur in other regions where Google operates.

How long we keep it

Lobby and presence data is transient and is removed when games end or after a short inactivity window. Account and deck data persists until you ask us to delete it or clear your browser storage.

Your rights

Under UK/EU data protection law you can ask us to access, correct, or delete your data, or object to our processing. To do this, contact us at blissettgeorge@gmail.com. You can also clear locally-stored data by clearing your browser storage for this site. You have the right to complain to the UK Information Commissioner's Office (ICO).

Children

Crucible Cards is not directed at children under 13, and we don't knowingly collect data from them. If you believe a child has provided us data, contact us and we'll remove it.

Cookies & local storage

We use browser local storage to keep you signed in and to store your decks and settings. We do not use third-party advertising or tracking cookies. For analytics we use Cloudflare Web Analytics and Umami, both of which are privacy-friendly: they do not use cookies, do not collect personal information, and do not track you across other websites. They record only anonymous, aggregated information such as page views, approximate location (such as country and region), referrer, and device or browser type, which helps us understand how the site is used.

Changes

We may update this policy as the project evolves. We'll change the "last updated" date above when we do.