Saffi Eriksdotter, Mistmoon Griffin, and Hammerhead, Maggia Boss

Prerequisites

• Saffi Eriksdotter on the battlefield
• Mistmoon Griffin on the battlefield
• Hammerhead, Maggia Boss on the battlefield

Steps

1. Activate Saffi by sacrificing it, targeting Mistmoon Griffin
2. Activate Hammerhead by sacrificing Mistmoon Griffin
3. When Mistmoon Griffin dies, it and Saffi trigger
4. Resolve the Saffi trigger, returning Mistmoon Griffin from your graveyard to the battlefield
5. Resolve the Mistmoon Griffin trigger, failing to exile it as it is not in your graveyard and then returning Saffi from your graveyard to the battlefield
6. Resolve the Hammerhead ability
7. Repeat

Results

• Infinite +1/+1 counters on a creature
• Infinite creature ETB
• Infinite creature LTB
• Infinite creature sacrifice triggers
• Infinite death triggers