The Time Above

Regardless of their duties within the warren, every Underdweller is brought to the surface on the first full dark (when neither moon is visible) after their fourteenth birthday. They must return to the surface each night and stay above ground from sunfall to sunrise until the first dual moon (when both moons are full).
This lengthy ceremony has noting to do with any religion. For a Darkling’s childhood years, they spend their entire time in caves with nothing but bioluminescent plants and glow spiders to see by. During the Time Above, an Underdweller’s eyes gradually grow accustomed to natural nightlight. Over he course of this time, the participating children build a large shelter together that can protect them in daylight if necessary, though they still reenter the warren during the day.
They are accompanied by their parents on the first night to celebrate their first view of the surface. After that, they travel above with a variety of instructors to explore their aptitude for tasks required for the continued survival of their warren. Whether it be foraging, hunting, chopping wood, or building, each person is evaluated by a master to see how they might best contribute as they transition from children’s tasks to adult responsibilities.
While these new adults are nervous about the judgement of their instructors, many carry a thirst to prove themselves. Moreover, the often feel like celebrities. Many Darklings who have surface duties stop to watch their progress and offer encouragement, though they are not allowed to give advice or assist in any way. They are also excited to see the surface for the first time. All their childhood they are told of the desolation above and the sunbeasts, but they feel like stories. They now can see the reality of the surface.
On the second-to-last night, the participants are required to witness a sunrise from the safety of the shelter they have built, and stay above ground and sleep in their shelter during that day. Many find this terrifying, but it is this moment when Darklings say that an Underdwelller has passed into adulthood. The following night, the dual moons, is a celebration, and the participants strike the shelter they built, symbolizing that they no longer require protection and can survive on their own.