Get your Horizon Zero Dawn theme for achieving the elusive platinum trophy and you should get an email from Sony with a code to unlock your new wallpaper.
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Now this is a great idea that other developers should look at! Sony is sending all North American players who achieve the Horizon Zero Dawn platinum trophy a code to unlock a special Horizon Zero Dawn PS4 theme.

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We’ve already seen some fantastic PS4 themes and wallpapers since Sony allowed users to upload their custom creations, but this particularly one looks to be a rather nice reward for completing Guerrilla Games’ PS4 exclusive adventure.

However, before you get too excited it seems that some players have yet to receive their codes to download the theme. According to Sony, you’ll get a mail once you’ve unlocked the platinum, so maybe you just have to sit and wait! Then again, we’ve seen a lot of players on Twitter in the UK complaining to Sony about not receiving their theme. Remember: the reward is for US players only!