New-to Amazon Prime (including trial) customers will enjoy 3 months (90 day) membership. Existing Amazon Prime (non-trial) customers will receive a AUD15 Amazon gift card directly into your Amazon wallet.
The exact same as this deal but now non-CommBank Mastercard holders can try and their luck. I was able to successfully get a $15 Amazon gift card. Note that some Platinum cards are actually World Mastercards.
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Update: If you don't have an eligible card, follow this comment thread for an easy loophole method. Full credit to doweyy
Once you are successful, to get $15 Amazon credit click "Sign in" as shown here. It will only add a $15 gift card to your account if you already have an active paid for Prime membership on that account. Trial Prime membership won't work - It will be replaced by 3 months membership.
Update 23/11: Up and working again for eligible MasterCard holders.
I was tempted to use the card generator but it just doesn't sit right with me for whatever reason
Will just pay for prime for Black Friday later on