Excava, the Risen Past, Solemnity, Breath of Fury, and Smellerbee, Rebel Fighter

Prerequisites

• Excava, the Risen Past on the battlefield
• Solemnity on the battlefield
• Breath of Fury on the battlefield
• Smellerbee, Rebel Fighter on the battlefield

Steps

1. Declare Excava and the creature with Breath of Fury attached as attackers
2. Excava triggers, returning up to one creature with mana value 3 or less from your graveyard to the battlefield
3. It won't enter with a finality counter on it due to Solemnity
4. Deal combat damage using the creature that has Breath of Fury attached
5. Breath of Fury triggers, causing you to sacrifice the creature it is attached to, then attach Breath of Fury to another creature with mana value 3 or less, then causing you to untap all creatures you control and to get an additional combat phase after this one
6. Repeat each combat phase

Results

• Infinite ETB
• Infinite LTB
• Infinite combat damage
• Infinite combat phases
• Infinite death triggers
• Infinite mana creatures you control can produce
• Infinite sacrifice triggers
• Infinite untap of creatures you control