Urabrask's Forge, and Breath of Fury

Prerequisites

• Urabrask's Forge on the battlefield
• Breath of Fury on the battlefield
• Breath of Fury attached to a creature you control that can attack this turn
• An opponent cannot block creatures you control

Steps

1. At the beginning of your combat phase, Urabrask's Forge triggers, putting an oil counter on it, and creating an X/1 Phyrexian Horror creature token with trample and haste
2. Deal combat damage to an opponent using the creature with Breath of Fury attached
3. Breath of Fury triggers, causing you to sacrifice the creature with Breath of Fury attached, then attach Breath of Fury to the Phyrexian Horror token and to get an additional combat phase after this one
4. Repeat each combat phase

Results

• Infinite combat damage
• Infinite combat phases
• Infinite death triggers
• Infinite ETB
• Infinite LTB
• Infinite mana creatures you control can produce
• Infinite oil counters on Urabrask's Forge
• Infinite sacrifice triggers
• Infinite untap of creatures you control