It wasn't hard to see that Claude was struggling. His shuddering was clear to see from where he stood. Maybe he should sit out the next exercise? No, he might find it offensive. 

Cayenne listened quietly to Castiel, his arms folded. When she finished, he shook his head slowly.
"Very good, all of you." He ignored Castiel's comment. "You found all my items, but there is one more out there. It is warded to be invisible, and since you are the most powerful here, Castiel, you can go first." With a nod toward the trees he knew none of them would be able to find the final item. Not until they gave up and looked down. Cayenne smiled, wondering if any of them would give up and see the rock sitting right on the stone wall in front of them.