So we meet for the first time Whose Expanse is this anyway ?
"Yes, I can. In fact that is what happened when I first gained this power, the power is called the Umbra. Yet when I reformed I wasn't me I was Millenia. It took a while before I came back. How does it work ? Well it is a natural force it is change, entropy, mutation, evolution and destruction. It is linked with me so it has become reflex almost."
A strange look overcame Skye for a moment, "Practical application ? Huh. You know I have been asked many things and helped a lot of people but I have never been asked that before. It is a strong force for destruction, so in a way it is a superior offensive power. It's opposite is a superior defensive power called Eidolon, I will get to that in a moment. At it's most simple levels I can perceive the Umbra in all things."
Skye proceeds to go around describing old wounds on each of the people here. As well as describing what there children may look like as natural evolution takes place.
"I can see the same weakness in walls, in computer programs, in conversations, philosophies. I see how entropy and change can effect things. It's useful but as you can imagine sometimes depressing so unlike some that share in the power I don't always actively use it. Millenia can explain Umbra really well she took to it like a fish to water."
Skye shakes her head slightly, "I am unsure. A seer or diviner might be able to use the Key in such a way. What I do know is a Warden can set their mind to finding something, or someplace and find it. It might take a while but unless another Warden is hiding what your looking for you should be able to find it as one."
Skye rolls her eyes looks at the ceiling and throws up her hands.
"The Grand Stair, or Yggdrasil, or The Maze, or any number of names this place has is ancient truly unimaginably ancient. I know some really ancient beings and they weren't even a twinkle in the eye of their great, great, great grand parents when the Grand Stair was already ancient. So I must confess I don't know who originally made them, but there are some hints as to why. Some claim to help keep things organized, some say Umbra was old and thus the early protoverse was a chaotic and planets and dimension struck each other in a grand mess. Then some being spoke ORDER and then their was the Eidolon and they saw it was good. This gave some order to things and something back then built the Grand Stair to separate things and give room for the many realities to not mix with each other and grow on their own. Every once in a while you might see some sigils near Doors those are known as Rhen Code the people who wrote them are ancient and they are one of the few who know how to actually leave marks on the Grand Stair that last. If you meet one they can perhaps answer your question better though they are very close lipped in general."
"Another thing the early universe had which strode the early dimensions as they clashed and merged and mingled before they were separated, were the mighty and terrifying Typhonians. Gigantic Titans of obscene power. I can testify these things are real not myth. The Grand Stair may have been invested to strand them in whatever world they were in when the Stair separated things. Doors were made to keep this megalithic beings from making use of the Stair."