Knowledge Pool + Moderation + Harmless Offering

Knowledge Pool

Moderation

Harmless Offering

How it works

1. Cast Harmless Offering by paying 2, giving control of Moderation to an opponent.
2. Cast Knowledge Pool by paying 6.
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.