If you un-link your Facebook account within the Facebook settings, it does not communicate with us that you have done so.
If you do this method, you will be unable to log back into Celtic Heroes unless you re-link using the same Facebook account.
You can always submit a ticket to Support if you wish to log-in using a username/password or if you are unable to log in using Facebook.
I've submitted a ticket asking support to allow me to use my username and password again but they said they dont offer that option...
Its extremely inconvenient to use facebook to log in because you have to type in your user and pass every time and when it changed the username on the login screen to your facebook name it still doesnt let you "continue" straight into the game- you still have to type in your FB username/password
How hard can it be to just set an option so player can revert back to logging in with their CH account details?