Ghyrson Starn, Kelermorph, Gisela, Blade of Goldnight, Sakashima the Impostor, and Harmless Offering

Prerequisites

• Ghyrson Starn, Kelermorph on the battlefield
• Gisela, Blade of Goldnight on the battlefield
• Sakashima the Impostor on the battlefield
• Harmless Offering in hand
• You have a way to deal exactly two or three damage to an opponent
• available

Steps

1. Cast Harmless Offering by paying its mana cost, giving control of Gisela to an opponent
2. Deal exactly two or three damage to the opponent, which is reduced to one by Gisela, triggering Ghyrson Starn and Sakashima the Impostor
3. Resolve the Ghyrson Starn trigger, dealing 1 damage to the opponent
4. Sakashima the Impostor triggers, dealing 1 damage to the opponent
5. Ghyrson Starn triggers, dealing 1 damage to the opponent
6. Repeat from step 4

Results

• Infinite damage to target opponent