Murderous Redcap, Good-Fortune Unicorn, and Phyrexian Altar

Prerequisites

• Murderous Redcap on the battlefield
• Good-Fortune Unicorn on the battlefield
• Phyrexian Altar on the battlefield

Steps

1. Sacrifice Murderous Redcap to Phyrexian Altar to add one mana of any color
2. Murderous Redcap's persist triggers, returning it to the battlefield
3. Murderous Redcap returns to the battlefield with a +1/+1 counter and a -1/-1 counter which cancel out
4. Murderous Redcap triggers, dealing 2 damage to any target
5. Repeat

Results

• Infinite colored mana
• Infinite damage
• Infinite death triggers
• Infinite ETB
• Infinite LTB
• Infinite sacrifice triggers