I hate hearing about things that hurt other people but I love it at the same time.
• Waterboarding
• Trepanning
• Giving him something that would make him hallucinate
• Temporary blinding
• Forcing him to get drunk/high
• Trapping him in a small room - like being buried alive
I hope some of these ideas are original, and I think
that the 5th one would be quite relevant to Gerard especially, if it wasn't unpleasant enough already.