Just all of the different traits of a feather sprite and their rarities. On the side it explains that 2 rare traits equals a very rare feather sprite, and two very rare traits equals an ultra rare feather sprite. Rarities from top to bottom are common, uncommon, rare, very rare, ultra rare and epic. Any custom wings, tails, or antennae makes it very rare, horns are ultra rare but I didn't add that to the list. No tail is ultra rare as well, and no feather sprite will be without wings.
