Cookies, briefly.

OUTLIER sets exactly one cookie: outlier_session. It’s first-party, HTTP-only, and holds a random token that links your browser to your game progress (as a guest) or your account (when logged in). There are no advertising or cross-site tracking cookies.

Because that cookie is strictly necessary to play, it doesn’t need consent under most cookie laws — but you can always clear it in your browser, which logs you out and forgets guest progress. Read the full privacy policy.