Key

In Season 5, Buffy's little sister Dawn was revealed to be The Key, a ball of mystical energy with the power to open Dimensions, which is why the villain, Glory went after her. If Dawn is The Key, does that mean that she may have mystical powers of her own? I know that Dawn didn't display any amazing powers like Willow did, but is it possible that she may have some hidden power to open dimensions all by herself? This is just a theory; but what do you think?

(References: Dawn Summers- Heroes- Wiki- Google Images)

We all know the moment. Powerful, emotional, an amazing end to an amazing season.

But one thing that doesn’t make sense to me when I think about it is why Buffy’s blood actually closed the portal.

Dawn was made from Buffy, their blood is the same, it worked the same way — I get that. But the specific requirements for closing the portal was that the Key’s blood had to stop flowing (or circulating, probably), not for all of it to fall into the portal.

And Dawn was still bleeding (and alive). If they’d have actually killed Dawn but without dumping her in the portal, would that work to close it, or would the world be in hell until they realised what they had to do?

The requirements were really unclear... though I guess that means there are lots of things to speculate about, too.

Was there a certain volume of blood needed? A certain percentage of the Key’s essence, which Buffy managed to trick?

...Thinking about that, that actually makes sense — but does anybody have any other theories? Or is there something I’m missing out?