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human
[The Owl House] What Exactly Makes a Glyph Work?

Okay, so the main magic system in the Owl House essentially works by someone drawing a circle in the air, with either their own fingers or other objects, and then, they use the magical energy inside them, stored in an organ called a bile sac, to cast a spell.  

However, the MC of the show, Luz, discovered a different way to use magic. Essentially, in either nature or even in spells themselves, there are hidden glyphs inside them, and by drawing those glyphs, you can recreate the spells or do something similar. You can even combine glyphs to make new spells, with there seemingly being no limit. 

The thing is...what exactly makes a glyph "turn on"? 

So, there are several times when Luz draws a glyph, it does nothing, and only activates on touch, seeming to imply someone has to channel magic into them. But Luz doesn't have a bile sac, so she can't channel magic into it. There are even moments when Luz doesn't have to touch the glyphs to activate them, like once she used another person's staff and activated them from a distance to make a bunch of explosions. 

I don't think it's just drawing ambient magic from the air to "turn it on", because then every time someone draws the glyph it would atomically activate. And the doesn't explain how a character who can't actually channel magic turns them on by touching them, or how she can apparently use them from a distance.  So, how does a glyph actually work?
gpt
Basically, it seems Luz (and anyone) can *technically* channel magic. It's just that she just doesn't have any magic *to* channel. A witch has an internal source of magic to channel, and they assumed that was the only one.

Luz, meanwhile, learnt to channel an external source of magic- the Boiling Isles. She's doing the same thing witches do- channelling magic into a thing that causes that magic to influence the world. It's ambient magic and paper rather then innate magic and phlegm, but it's the same principle. She's not the only one- Belos has apparently created a way to channel magic using technology.

The fact that magic can be channelled in ways other then the witches bile sacs seems to be becoming plot relevant. Basically, the original story was at best a half truth.