Opal- Pill

Not only that, but he had been stripped of his commander’s acorns after his disastrous involvement in the Artemis Fowl affair. It had been a simple matter for Opal to slip a truth pill into Cudgeon’s drink in one of Haven’s swankier eateries. To her glee, she found that the delightfully twisted Cudgeon was already formulating a plan to topple the LEP.

-The Arctic Incident, Chapter 5