Board Thread:General Discussion/@comment-25926288-20151116014923/@comment-25926288-20160216022425

Finally rewatched and I think I figured out what the writers and producers were going for with "How another Dark One was made".

The Dark Swirly stuff is the magic of the Holy grail. The HG magic was not to be accessed by those without pure hearts. So, when the HG magic went into Hook, it immediately turned him into a Dark One simply because he has darkness within his heart, whereas Merlin's was full of light. I know it was colored black, but black doesn't mean Dark Magic as Light and Dark magic aren't distinguishable by colors as the default magic color is purple.

Chances are the HG contained "terrible power" only to be wielded by one with a pure heart. Doesn't explain the vault and how the Jungle Dimension connects to everything, but there's a step!

So, my theory is that the Dark swirly stuff isn't the Darkness of the collective Dark Ones, but the Holy Grail magic.