Appa, Steadfast Guardian, Ashnod's Altar, and Dance of the Dead

Prerequisites

• Appa, Steadfast Guardian in the graveyard
• Ashnod's Altar on the battlefield
• Dance of the Dead in hand
• available

Steps

1. Cast Dance of the Dead by paying its mana cost, returning Appa from your graveyard to the battlefield with Dance of the Dead attached to it
2. When Appa enters, it triggers, airbending Dance of the Dead
3. Dance of the Dead triggers
4. Holding priority, activate Ashnod's Altar by sacrificing Appa, adding
5. Resolve the Dance of the Dead ability, doing nothing
6. Cast Dance of the Dead from exile by paying , returning Appa from your graveyard to the battlefield with Dance of the Dead attached to it
7. Repeat from step 2

Results

• Infinite creature ETB
• Infinite creature LTB
• Infinite creature sacrifice triggers
• Infinite death triggers
• Infinite storm count