It is was what I thought at the was a watch-wher. As of Book 2, I now understand that these are a different variety of dragon than the ones bred to fight thread. But it made sense at the time, a green dragon, the most common and least impressive variety, with clipped wings so they couldn't fly and chained so they couldn't go anywhere. I also did know at the time that dragons could go between, so it wasn't a consideration. Enjoy.