Frumpkin sniffs and jumps over to Essek's shoulder with a practiced leap, scarfing around his neck and purring.

"Generally it can't be too massive - so I could turn into an owl big enough to carry someone, but not one much bigger than that. Transmutation is generally very temporary. The magical weave that composes the spell isn't strong enough to hold things for very long. There are some more permanent spells, but those generally require a larger dose of materials for the spell to work - not something that you can carry around."

He holds the cocoon out to Elidibus - it's dried but not extremely fragile. There's a hole where the butterfly emerged from, but otherwise it's fully intact. "I believe you wanted to examine this." Though for all Caleb has done with it, it appears to simply be an ordinary cocoon one would find anywhere.