Twinflame, Priest of Urabrask, Returned Pastcaller, and Return the Favor

Prerequisites

• Twinflame in hand
• Priest of Urabrask on the battlefield
• Returned Pastcaller on the battlefield
• Return the Favor in hand
• available

Steps

1. Cast Twinflame by paying , targeting any two creatures
2. Holding priority, cast Return the Favor by paying its mana cost, copying Twinflame, with the copy targeting Priest of Urabrask and Returned Pastcaller
3. Resolve the copy of Twinflame, creating a token copy of Priest of Urabrask and Returned Pastcaller with haste
4. When the Priest of Urabrask and Returned Pastcaller tokens enter, they trigger
5. Resolve the Priest of Urabrask trigger, adding
6. Resolve the Returned Pastcaller trigger, returning Return the Favor from your graveyard to your hand
7. Repeat from step 2

Results

• Infinite LTB
• Infinite ETB
• Infinite storm count
• Infinite red mana
• Infinite creature tokens with haste
• Infinite magecraft triggers