Rith, the Awakener, Breath of Fury, Phyrexian Altar, and Urabrask the Hidden

Prerequisites

• Rith, the Awakener on the battlefield
• Breath of Fury on the battlefield
• Phyrexian Altar on the battlefield
• Urabrask the Hidden on the battlefield
• There are at least four permanents of any color on the battlefield
• Breath of Fury attached to any creature you control except Rith or Urabrask the Hidden
• An opponent cannot block creatures you control
• available

Steps

1. Deal combat damage using Rith and the creature with Breath of Fury attached, triggering Rith and Breath of Fury
2. Resolve the Rith trigger, causing you to pay to create at least four 1/1 Saproling creature tokens
3. Resolve the Breath of Fury trigger, causing you to sacrifice the creature it is attached to, then attach Breath of Fury to a Saproling token, then causing you to untap all creatures you control and to get an additional combat phase after this one
4. Move to your next combat phase, and deal combat damage using Rith and the creature with Breath of Fury attached, triggering Rith and Breath of Fury
5. Holding priority, activate Phyrexian Altar three times by sacrificing three Saprolings, adding
6. Repeat from step 2

Results

• Infinite colored mana
• Infinite combat damage
• Infinite combat phases
• Infinite death triggers
• Infinite ETB
• Infinite LTB
• Infinite mana creatures you control can produce
• Infinite sacrifice triggers
• Infinite untap of creatures you control
• Infinite creature tokens with haste