The only offer I am aware of with that movie and to get a bonus avatar prop is the one Xbox LIVE Rewards is offering. Is this the offer you are referring to
The Dark Knight Rises Sweepstakes?
According to the Xbox LIVE Rewards
FAQ an email with a token will be sent to the email address as listed on your account
HERE by January 18th, 2013
There is an Xbox LIVE Rewards specific forum that can be found
HERE. They might be able to offer further help if this is the offer you are trying to get.
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