Many of the best traps are simple. You just have to think about it, and hope your victim doesn't.

“I haven't devoured a soul in...What month is this? March?”

“But Grover’s voice was already growing fainter. ‘Sweet dreams. Don’t let me die!”

“The future for Commander Tool Belt was not looking so hot.”

“I know you'll do what's best for Annabeth.""How can you be sure?""Because she'd…”