Knowledge Pool, Moderation, and Harmless Offering

Prerequisites

• Knowledge Pool in hand
• Moderation on the battlefield
• Harmless Offering in hand
• available

Steps

1. Cast Harmless Offering by paying , giving control of Moderation to an opponent
2. Cast Knowledge Pool by paying
3. Whenever the opponent that controls Moderation casts a spell from their hand, Knowledge Pool triggers, exiling that spell
4. Because Moderation prevents the opponent from casting more than one spell each turn, the opponent cannot cast the spell permitted by Knowledge Pool, or any other spell that turn

Results

• Exile all spells cast from target opponent's hand
• Target opponent can only cast one spell per turn