Retreat to Emeria, Haru, Hidden Talent, and Treva's Ruins

Prerequisites

• Retreat to Emeria on the battlefield
• Haru, Hidden Talent on the battlefield
• Treva's Ruins in hand

Steps

1. Play Treva's Ruins
2. When Treva's Ruins 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 Treva's Ruins
5. Resolve the Treva's Ruins trigger from step 2, causing you to sacrifice it Haru triggers, returning Treva's Ruins 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