Tana, the Bloodsower, Breath of Fury, and Fervor

Prerequisites

• Tana, the Bloodsower on the battlefield
• Breath of Fury on the battlefield
• Fervor on the battlefield
• Breath of Fury attached to any other creature you control that can attack this turn
• Tana does not have summoning sickness
• An opponent is unable to block and kill your creatures

Steps

1. Deal combat damage with Tana and the creature that has Breath of Fury attached
2. Tana and Breath of Fury triggers
3. Resolve the Tana trigger, creating a number of 1/1 Saproling creature tokens equal to the damage Tana dealt
4. Resolve the Breath of Fury trigger, causing you to sacrifice the creature it is attached to, attach Breath of Fury to a Saproling token, untap all creatures you control and get an additional combat phase after this one
5. Repeat

Results

• 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