Ajact: Ascend chain.
You might not be able to do that. There are real actual adult mydians here, and it looks like there's been some kind of fight, which maybe means they were fighting the horrible rainbow fire things. It probably isn't even safe to be here. It seems a lot like these people have built a forward operating base around a giant chain harpoon gun that let the rainbow shade(s) onto Prospit to set the whole thing on fire.