For 20 Farm Cash, you can purchase a single Zoo Mystery Crate, which will contain one of the following:
This Zoo Mystery Box will only be available for the next five days, so while you may be tempted to purchase six of these boxes to be done with it (and have a full set of animals), keep in mind that duplicates are possible, and there's no telling just how many boxes you'll need to actually purchase before it's all said and done. Good luck if you're going for one specific animal of the six, or if you'd like a complete set without breaking the bank!
Which of these six animals is your favorite? Do you already have some of these animals on your farm? Let us know in the comments.