Yedora, Grave Gardener, Granite Witness, Skirk Alarmist, and Phyrexian Altar

Prerequisites

• Yedora, Grave Gardener on the battlefield
• Granite Witness on the battlefield
• Skirk Alarmist on the battlefield
• Phyrexian Altar on the battlefield
• Skirk Alarmist does not have summoning sickness

Steps

1. Activate Phyrexian Altar by sacrificing Granite Witness, adding one mana of any color
2. When Granite Witness dies, Yedora triggers, returning Granite Witness from your graveyard to the battlefield face-down as a Forest land
3. Activate Granite Witness by tapping it, adding
4. Activate Skirk Alarmist by tapping it, turning Granite Witness face-up
5. Granite Witness triggers, untapping Skirk Alarmist
6. Repeat

Results

• Infinite colored mana
• Infinite death triggers
• Infinite landfall triggers
• Infinite LTB
• Infinite sacrifice triggers