What are this?

there are no markings on her country roads no signs that show the way back home Waker's mention of the unknown land on the other sound of the mountain had made Otem curious. Of course he probably meant on the other other side of the Pinnacle, but as soon as the words had reached her ears, it had made Otem wonder. And so she had to see for herself. The barrier, or boundary or whatever they were supposed to call it (veil? wall? curtain? border?) was not what she had expected. She couldn't fly over it, but at the time time, it wasn't like there was a wall of black reaching up into space. It just sort of...was, and at her current flying altitude it was as if her body just knew that it was impermeable. But what about closer to the ground, where it was dense and dark? Lowering herself right close to where land disappeared under the ledge of black, Otem landed and halted. Looking around, she spied a small pebble near one of her hooves and kicked it towards the wall. Shockingly, it seemed to go right through and pass completely out of sight. This it did without any sort of sound or visual cue that anything out of the ordinary had happened. And yet at the same time, a small grasshopper continually bounces off of the black shadows. "What?"  Otem mumbled to herself, confused about the metaphysics of this wall that was presumably part of the Rift sickness. The mare glanced at the orb hovering gently at her side. "And you can't do anything about it?" She asked rhetorically, before turning her gaze back to the black shadows.

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