Not truly necessary to read the first story.
Ever since a creature entered a bar in the arid south, rumors have started growing about the existence of broods other than Chrysalis'. Several hopefuls proving it and cynics disproving it have created somewhat of a division between the small groups that have heard of the rumors and cared enough.
While not that prominent, the rumors still reached the more adventurous of ponies, and one mare decides to look for a brood in the dry, dark base of a mountain range. All that's left is to figure out if they were never found because they don't exist, were skilled enough to hide themselves in plain sight, or because those who found them were never allowed to leave.