Earthcraft, Keeper of Progenitus, and Sliver Queen

Prerequisites

• Earthcraft on the battlefield
• Keeper of Progenitus on the battlefield
• Sliver Queen on the battlefield
• available

Steps

1. Activate Sliver Queen by paying , creating a creature token Activate Earthcraft by tapping the creature token, untapping a basic Mountain, Forest or Plains
2. Activate the land by tapping it, adding Keeper of Progenitus triggers, adding Repeat

Results

• Infinite ETB
• Infinite tapped creature tokens