Redeem codes in-game

Hi,

I can't find clearly the information in the guidelines so I ask it there, is it allowed to have a section in my games where people can use coupon code to redeem gifts ? For example a new hero is added, bam I distribute on my social networks a coupon code to use in-game to get 300 diamonds and 20,000 gold

This is something I saw on multiple games on the app store and I want to be sure i'm allowed to do it without being shutdown.

The guidelines mentions unlocking content or features or packs ( so that's not those 3 things ).

Best Regards, Hugo

Redeem codes in-game
 
 
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