Oath of Teferi +Aminatou, the Fateshifter +Spark Double +

Infinite ETBs Infinite Mana Revised by CR

Oath of Teferi allows each Planeswalker to activate their abilities twice Cast Spark Double as a copy of Aminatou Activate Aminatou's +1 ability to blink a land, respond by tapping it to add mana. Activate Spark Double's ability to blink Aminatou Activate Spark Double's ability to blink a land, tap it to add mana. Activate Aminatou's ability to blink Spark Double Repeat the process.

Legallity