So far I've tried it with wifi, without wifi, deleted and re installed the app, cleared the cache, reset my router, and all these dumb steps, still doesn't work.
- Enable 'auto sync' for 'Google Play Services': 'Settings' > 'Accounts' > 'Google' > Your Account > 'Google Play Services' > Check & Sync All
- Clear 'Google Play Games' cache and data: 'Settings' > 'Application Manager' > 'All' > 'Google Play Games' > Clear Cache & Data
- Clear 'Google Play Services' cache and data: 'Settings' > 'Application Manager' > 'All' > 'Google Play Services' > Clear Cache & Data
- Uninstall 'Google Play Games' updates: 'Settings' > 'Application Manager' > 'All' > 'Google Play Games' > Uninstall Updates, Clear Cache & Data
- Restart phone.
- Clear 'Google Play Store' cache and data: 'Settings' > 'Application Manager' > 'All' > 'Google Play Store' > Clear Cache & Data
- Clear 'Download Manager' cache and data: 'Settings' > 'Application Manager' > 'All' > 'Download Manager' > Clear Cache & Data
- Enable 'Download Manager' AND/OR 'Downloads': 'Settings' > 'Application Manager' > 'All' > 'Download Manager' AND/OR 'Downloads' > Enable (If Disabled)
- Update 'Google Play Games': 'Play Store' > Search 'Google Play Games' > 'Update' (if available)
- Restart phone.
- Attempt to authenticate with Star Wars: Galaxy of Heroes.