Game of War app is a Machine Zone company and you have to email them to remove your information.
On their site they say – “If you no longer want Machine Zone to make active use of your information, you may send an e-mail to firstname.lastname@example.org. Place “Delete My Account” in the subject line and include your first name, last name, e-mail address and user ID number from which you access our games (if applicable) in the body of the e-mail. We will respond to your request within thirty (30) days. Please note that certain records, for example those pertaining to payments or customer service matters, will be retained for legal and accounting purposes. If you have sent or posted content on the Service, We may not be able to delete it. ”
You can email them at email@example.com