someone should make a prequel mod where you can be that big rock and call the game "Big labyrinth rock story" and your goal is to go to that boulder chamber area and sit there
Seems like a Shide (zig-zag paper streamer often used in Shinto rituals) connected to a Shimenawa "enclosing rope". Probably to act as a ward against outside influence, or a ritual purification? I mean beyond the warded boulder was not only the hostile "heart of the island", but countless dead robots. According to the Gaudi, a witch, likely Jenka created the labyrinth and tasked the Gaudi to keep the Core safe.
Yeah the shide-adorned shimenawa is what got me curious, isn't it also done to allow spirits to stay in the adorned stone?
It would be intriguing if it was actually meant as a seal to keep Ballos in, but that might just be unlikely.
Well, Jenka/??? appear to create powerful seals. The Seal chamber filled with the dead that keep Ballos in. The Sunstone blocks that were closed until Omega(?) was defeated. The heavy press(?) that kept a direct path to Ballos sealed. The boulder to the Core area. The warehouse that needed a key even for Misery/Balrog. Balrog does seem special though, able to break through the seal chamber/boulder. Who knows!
The seals on the boulder are probably meant to stop people from using magic to move it. Balrog was likely able to move the boulder because he moved it by conventional means, which would have been considered extremely unlikely back when Jenka put it there (under the assumption that it was her that put it there).
That's actually a pretty fair point, if anybody could just move the boulder by ease they could reach the core, destroy it and release Ballos in the resulting crash.
When magic isn't an option there isn't much way to move it without superhuman strength (like apparently Balrog's) and who knows how long the boulder's been there, might as well have been in a time machines weren't a thing.