Insulation. It seemed like a dead useful spell to use, especially since Mo intended to go yeti hunting in the future. The very near future. He was basically already living in the coldest he could ever remember being. It was good practice, that was for sure, and this spell was one he really needed to master.

As soon as they were let loose, Mo started trying out the incantation. Caelum Saepio. It was a doozy, what will all those diphthongs, so he worked it out slowly. "Cay-lum Say-pee-oh. Caelum Saepio." Was it possible to apply multiple strengths? Multiple applications? Hmm... experimentation was needed.