Opposition Agent, Sudden Substitution, and Selective Memory

Prerequisites

• Opposition Agent on the battlefield
• Sudden Substitution in hand
• Selective Memory in hand
• An opponent controls a creature
• available

Steps

1. Cast Selective Memory by paying
2. Holding priority, cast Sudden Substitution by paying , exchanging control of Selective Memory and target creature an opponent controls
3. Resolve Selective Memory, choosing to have the opponent exile all nonland cards in their library due to Opposition Agent

Results

• Exile all nonland cards from target opponent's library, with the ability for you to play them from exile