Saffi Eriksdotter, Mistmoon Griffin, and Phyrexian Altar

Prerequisites

• Saffi Eriksdotter on the battlefield
• Mistmoon Griffin on the battlefield
• Phyrexian Altar on the battlefield
• undefined

Steps

1. Activate Saffi by sacrificing it, targeting Mistmoon Griffin
2. Activate Phyrexian Altar by sacrificing Mistmoon Griffin, adding one mana of any color
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. Repeat

Results

• Infinite LTB
• Infinite ETB
• Infinite colored mana
• Infinite sacrifice triggers
• Infinite death triggers