Appears to be a long running deal but not currently posted here that I can see.
Book any Emirates flight originating from any Australian destination and enjoy the following savings thanks to Mastercard.
5% discount off Economy/Business Class Saver fares
8% discount off Economy/Business Class Flex fares
This offer is only valid for online bookings.
The discount applies to airfare charge only. Fuel surcharge and third-party taxes are not discounted.
This offer is valid for Mastercard Australia holders who purchase and complete issuance of a ticket between 1 April 2018 and 30 September 2019, as per the 'Date of Issue' on the e-ticket receipt booked online at emirates.com/au using promo code AUMCC17, with Mastercard used as the form of payment.
I actually tried paying direct transfer and still managed to use the discount code