Satoru Umezawa, Palinchron, and Great Whale

Prerequisites

• Satoru Umezawa on the battlefield
• Palinchron in hand
• Great Whale on the battlefield
• Great Whale does not have summoning sickness and cannot be blocked and killed by an opponent
• You control up to seven lands that can tap to produce at least

Steps

1. Declare Great Whale as an attacker
2. When Great Whale is unblocked, activate up to seven lands you control by tapping them, adding at least
3. Activate Palinchron's ninjitsu ability by paying and returning Great Whale from the battlefield to your hand, putting Palinchron from your hand onto the battlefield tapped and attacking
4. Palinchron enters the battlefield, untapping up to seven lands
5. Activate up to seven lands you control by tapping them, adding at least
6. Activate Great Whale's ninjitsu ability by paying and returning Palinchron from the battlefield to your hand, putting Great Whale from your hand onto the battlefield tapped and attacking
7. Great Whale enters the battlefield, untapping up to seven lands
8. Repeat from step 2

Results

• Infinite ETB
• Infinite LTB
• Infinite mana lands you control can produce
• Infinite untap of lands you control