That may be, but notice the posture of the king and how the people directed themselves to the wizard? The turtle might've been the source, but also he was part of the crown and was told to do so by the mad wizard. Notice how he doesn't care for the emerald? He was probably forced to do it.

I might've been too high when I was watching this episode, but did anyone else notice what had turned the people into sand?
It appeared to be an old man with a crown being attacked and/or being attacked by the people of the kingdom. Also, that old man appeared to be some sort of wizard and with a crown that seems(ed)…