WiFi Duel uses Firebase Realtime Database to match players. Takes about 3 minutes to set up.
2Inside your project: Build → Realtime Database → Create Database (start in test mode).
3Go to Project Settings → General → Your apps, click </> and copy your config.
4Open this file in a text editor, paste your config values into firebaseConfig in the script.
5In Realtime Database → Rules, paste:
{"rules":{".read":true,".write":true}}
⚠ This opens all access. Fine for testing — tighten later.