Xyris, the Writhing Storm, Breath of Fury, and Fervor

Prerequisites

• Xyris, the Writhing Storm on the battlefield
• Breath of Fury on the battlefield
• Fervor on the battlefield
• Breath of Fury attached to any other creature you control
• An opponent is unable to block and kill your creatures

Steps

1. Deal combat damage with Xyris and the creature with Breath of Fury attached
2. Xyris and Breath of Fury trigger
3. Resolve the Xyris trigger, causing you and the opponent dealt combat damage to draw cards equal to the damage dealt by Xyris
4. Xyris triggers for each card the opponent draws, creating that many 1/1 Snake creature tokens
5. Resolve the Breath of Fury trigger, sacrificing the enchanted creature, attaching Breath of Fury to a Snake token, untapping all creatures you control and getting an additional combat phase after this one
6. Repeat

Results

• Infinite card draw
• Infinite draw triggers
• Near-infinite combat phases
• Near-infinite creature tokens with haste
• Near-infinite death triggers
• Near-infinite ETB
• Near-infinite LTB
• Near-infinite sacrifice triggers
• Near-infinite untap of all creatures you control