A talented Gwent fan has released an unofficial card editor for CD Projekt's Witcher-based collectible card game Gwent. It's named Custom Gwent, sensibly enough, and it allows you to design your own cards by picking from a bunch of different properties—oh and by adding your own background images.
Creator Owmince has spent the last 10 days working on the site, a site they make clear is "not approved or endorsed by" CD Projekt Red (although the official Gwent twitter account appears to be fond of it). Approved or not, they'd be fools not to incorporate some of the designs into the official game. For example, PC Gamer's deputy editor Phil Savage has designed a card that would be the undisputed star of any Gwent collection:
You can download that beauty at the previous link, or if you want to make your own you can do that here.