Since Zynga Slingo is a bit different than other games, you won't be asked to play until you reach a specific level as in so many other cross-promotions. Instead, you'll be asked to play Zynga Slingo until you've earned 30 different Medals. There are five Medals up for grabs on each particular level, with these Medals being awarded after you've earned different amounts of points or have filled your Slingo Card completely.
Once you've earned the 30 Medals necessary for this promotion, you can simply jump back into FarmVille where you'll be rewarded three free Mystery Darts. These Darts are individually worth anywhere from 16 to 20 Farm Cash, and will practically guarantee that you receive three cool animals or decorations for your farms. If they work as other Game Darts do (we have no reason to think they won't), you'll even be able to save them up until the prizes in a particular week's Mystery Game really suit your style!
Conveniently enough, you also need to reach the 30 Medal mark to finish the Hidden Chronicles promotion, so if you've already made it that far, you won't have to do any extra work here. That will likely be the number to hit as these cross promotions roll out to other games, but we'll make sure to update you if you need to earn more or less. Stay tuned!
What do you think of this Zynga Slingo promotion in FarmVille? Sound off in the comments.