Retreat to Emeria, Haru, Hidden Talent, and Cabaretti Courtyard

Prerequisites

• Retreat to Emeria on the battlefield
• Haru, Hidden Talent on the battlefield
• Cabaretti Courtyard in hand

Steps

1. Play Cabaretti Courtyard
2. When Cabaretti Courtyard 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 Cabaretti Courtyard
5. Resolve the Cabaretti Courtyard trigger from step 2, causing you to sacrifice it, search your library for an applicable land and put it onto the battlefield tapped, and gain 1 life
6. Haru triggers, returning Cabaretti Courtyard from your graveyard to the battlefield
7. Repeat from step 2

Results

• Infinite ETB
• Infinite lifegain triggers
• Infinite lifegain
• Infinite creature tokens
• Near-infinite landfall triggers
• Infinite landfall triggers
• Put all basic Mountains from your library onto the battlefield tapped
• Put all basic Forests from your library onto the battlefield tapped
• Put all basic Plains from your library onto the battlefield tapped