The answer is another snowball, a little smaller than a tennisball. The real answer can be seen scooting around in the remaining snow under the nearest mushroom-like stone formation. It's an Eeno, barely a foot tall. There's another smaller one nearby, and a few shifting bits of snow that might be others.

Mistral just stares for a moment and shakes his head as if he can't believe what he's seeing. "They've shrunk. They're melting along with the snow."