Kenrith, the Returned King, Earthcraft, Agatha of the Vile Cauldron, and Repository Skaab

Prerequisites

• Kenrith, the Returned King on the battlefield
• Earthcraft on the battlefield
• Agatha of the Vile Cauldron on the battlefield
• Repository Skaab in the graveyard

Steps

1. Activate a basic Swamp by tapping it, adding
2. Activate Kenrith's fifth ability by paying due to Agatha, returning Repository Skaab from your graveyard to the battlefield
3. When Repository Skaab enters, its exploit ability triggers
4. Holding priority, activate Earthcraft by tapping Repository Skaab, untapping the basic Swamp
5. Resolve the Repository Skaab ability, sacrificing it
6. Repository Skaab's second ability triggers, returning an instant or sorcery from your graveyard to your hand
7. Repeat

Results

• Infinite ETB
• Infinite LTB
• Infinite death triggers
• Infinite sacrifice triggers
• Return all instant and sorcery cards from your graveyard to your hand