Uhhh... why would they? There's plenty of light around, isn't there?

[Geir glances up and then back to Roxas in confusion. SUN SEEMS TO BE THERE!]

I don't know about the hearts of the worlds, either. This sounds like a your-world thing... or maybe a your-universe thing. What is it?

[the idea that there are other universes with different rules was a great relief in all these conflicting explanations of how different peoples' rules for magic operate. Geir's glad that Terezi explained that one to him.]