Urza, Lord High Artificer, Pili-Pala, and Heartstone

Prerequisites

• Urza, Lord High Artificer on the battlefield
• Pili-Pala on the battlefield
• Heartstone on the battlefield
• Pili-Pala does not have summoning sickness

Steps

1. Activate Urza's first ability by tapping Pili-Pala, adding
2. Activate Pili-Pala by paying and untapping it, adding one mana of any color
3. Repeat
4. Once you have infinite mana, you may use it to activate Urza's ability

Results

• Cast all cards in your library without paying their mana costs
• Infinite colored mana
• Exile your library