Bwahhhh sorry I've been busy today, yesterday was my birthday. Anyways, excited to get back to this and see more requests!

Witch: Someone who manipulates, changes, and breaks the rules of their aspect. They also seem to have a tendency to cooperate with powerful forces that either have a great deal of power over their aspect, or can affect their aspect in some way.

Light: Knowledge, particularly narrative knowledge and narrative importance (spotlight), fortune, luck, literal light, foresight, literal sight. Often associated with emotional instability, likely due to the trope of people going mad when they've attained too much knowledge.

So, a witch's purpose is to directly screw with their aspect and break it apart. They might work with or convince a powerful force to do something for them in order to accomplish this, or, a powerful force might have the witch do something for them. Damara worked on behalf of LE, Feferi convinced the Horrorterrors to create the dream bubbles, and Jade helped Alt Calliope. I wanted to elaborate a little extra here since I think a lot of people tend to simplify witches down a lot when they don't understand the narrative aspect of classpecting.

Most witches would be incredibly powerful but a Witch of Light would be up there with the most ridiculous. However, their powers would be incredibly abstract.

The most straightforward aspect of their powers would be the ability to manipulate luck. If they're powerful enough, they could sway any single thing that's up to chance even a little bit in their favor. They would also have a lot of influence over the narrative of their story itself. If they were someone who didn't enjoy responsibility or having people paying attention to them, they could subconsciously influence the story into not focusing on them very much, literally making themselves unimportant. Same is true for the opposite.

The ability to manipulate knowledge is where the powers could be interpreted in different ways, but I'll just go with my own ideas for it. A Witch of Light would have the ability to hide knowledge from others. Doing something like this, as well as what I mentioned earlier with them being able to keep the narrative spotlight off of them, are things they do because they simply will it to happen. If they focused on trying to hide knowledge from someone, the way that would work is that a bunch of unrelated things happen to keep them in the dark. Things that were going to happen anyway but only happened because she willed it to.

An extremely powerful Witch of Light might be able to fuck with the narrative to an even bigger extent. For example, if something happens in the story that should have a substantial impact on things, they could will it to be that it's entirely inconsequential regardless of how illogical that would be, therefore playing into a witch's ability to break their aspect. For example, a war breaks out that should change the culture of the world forever, but after it's over, everything simply returns back to normal, as if it never happened. People brush it off and seem to be unable to comprehend that things probably should have played out differently.

As for the part about Witches having a tendency to be involved with incredibly powerful or godlike forces, a Witch of Light might just be able to talk directly to the narrator or the author of the story itself, or they could come into contact with a full fledged Lord or Muse of Light from a different universe.