Knowledge Pool, Colfenor's Plans, and Harmless Offering

Prerequisites

• Knowledge Pool on the battlefield
• Colfenor's Plans on the battlefield
• Harmless Offering in hand
• available

Steps

1. Cast Harmless Offering by paying , giving control of Colfenor's Plans to an opponent
2. Whenever the opponent that controls Colfenor's Plans casts a spell from their hand, Knowledge Pool triggers, exiling that spell
3. Because Colfenor's Plans 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
• Target opponent skips their draw step