I really like the Quetzalcoatl! He is the funniest Elder so far, besides Areop-Enap. I like how he behave with Mach and Billy, especially his flashing temper. How calm he is when face Mach and second later he's angry to Billy. That's so funny.
I think he has a great power, maybe Earth elemental magic, because Black Hawk said last time he's angry was in 1906 (or 1907?), and after I search, there was a great earthquake at that time (although other source claims that it's Dee who caused the earthquake). Maybe Kukulkan will teach one (or both!) of the twin how to master Earth. Who knows? I certainly want to watch him again!
I also have a feeling that Kukulkan is connected to Anasazi people somehow. Remember that America has became Kukulkan's base since the Fall of Danu Talis. Billy had an Anasazi pot before, and Kukulkan has Black Hawk, a Native American as his servant.
It's so intriguing...