Note: You don't need to be a customer to use the following tools.
If you wish to use the two-factor authentication on your gameforge account without having to use the proprietary app made by gameforge...
./nja 2fa register -u [email protected] -p gameforge_password
~/.ogame/2fa
or the output of ./nja 2fa show -u [email protected]
./nja 2fa code -u [email protected]
./nja 2fa ls
./nja 2fa deregister -u [email protected]
You can now use Google Authenticator instead of gameforge app.