1. Navigate to Lists > Search > Saved Searches > New > Case.
2. In the Criteria tab > Standard, add the filters:
a. Status is Reopened
b. Awaiting Support Reply is True
3. In the Results tab, add the fields to be included in the body of the email (ex: Number, Subject, Company, Assigned To, Message Text).
4. In the Email tab > Recipients from Results, mark the Send on Update checkbox.
5. Add Assigned To under Recipient Field.
6. Click on Save.