Shadowspear, Harmless Offering, and Lich's Mastery

Prerequisites

• Shadowspear on the battlefield
• Harmless Offering in hand
• Lich's Mastery on the battlefield
• You have a way to cause Lich's Mastery to leave the battlefield
• available

Steps

1. Cast Harmless Offering by paying , giving an opponent control of Lich's Mastery
2. If needed, activate Shadowspear by paying , causing all permanents your opponents control to lose hexproof and indestructible until end of turn
3. Cause Lich's Mastery to leave the battlefield
4. Lich's Mastery triggers, causing its controller to lose the game

Results

• Target opponent loses the game