Retreat to Emeria, Haru, Hidden Talent, and Rith's Grove

Prerequisites

• Retreat to Emeria on the battlefield
• Haru, Hidden Talent on the battlefield
• Rith's Grove in hand

Steps

1. Play Rith's Grove
2. When Rith's Grove enters, it and Retreat to Emeria trigger
3. Resolve the Retreat to Emeria trigger, creating a 1/1 Kor Ally creature token
4. When the Kor Ally enters, Haru triggers, earthbending Rith's Grove
5. Resolve the Rith's Grove trigger from step 2, causing you to sacrifice it Haru triggers, returning Rith's Grove from your graveyard to the battlefield
6. Repeat from step 2

Results

• Infinite ETB
• Infinite lifegain triggers
• Infinite lifegain
• Infinite creature tokens
• Infinite landfall triggers