Privacy Policy

Last updated October 28, 2026

Short version: we keep only what the game needs to run your account. No ads, no trackers, no selling or sharing your data.

What we collect

Account: your username, your email address, and your password. The password is stored only as a salted, one-way hash, so nobody (including us) can read it.
Game data: your cards, team, gold, progress, battles, trades, friends and the other things you do in the game.
Sign-in session: when you log in on the web, a cookie holds a random session key so you stay logged in. On our side only a hash of that key is stored. Sessions end when you log out or after 30 days unused.
Network address: used to limit repeated sign-in and sign-up attempts (protection against password guessing). These counters are deleted within a day.
Last seen: the time you were last active, so friends can see whether you're online.

What we use it for

Only to run the game: logging you in, saving your progress, matching battles, showing friends and leaderboards, and keeping accounts safe. Your email is used for your account (for example, password resets once that's available). We don't send marketing email.

What other players can see

Your username, level, chosen picture card, team, and leaderboard results. Your email address is never shown to other players.

Where it's stored

The game runs on Cloudflare (Workers and D1 database), which processes the data on our behalf. We don't use analytics, advertising or tracking services, and the web version loads nothing from other sites.

Browser storage

Besides the sign-in cookie, the web version keeps a few small settings in your browser (music and sound on or off, which cards you've already seen). They never leave your device.

Deleting your data

You can delete your account at any time from Profile → Delete account. That removes your account and its game data right away. You can also change your email from your profile.

Children

HoloSynth isn't meant for children under 13, and we don't knowingly collect data from them. If you believe a child under 13 has an account, email support@holosynth.app and we'll delete it.

Changes

If this policy changes, we'll update the date above. Big changes will be announced in the game.

Contact

Questions or requests about your data: email support@holosynth.app.