Great Whale + Shrieking Drake + Panharmonicon

Great Whale

Shrieking Drake

Panharmonicon

How it works

1. Activate up to seven lands by tapping them, adding at least 2.
2. Cast Great Whale by paying 5.
3. When Great Whale enters the battlefield, it triggers twice.
4. Resolve the first trigger, untapping up to seven lands.
5. Holding priority, activate up to seven lands by tapping them, adding at least 2.
6. Resolve the second Great Whale trigger, untapping up to seven lands.
7. Cast Shrieking Drake by paying .
8. When Shrieking Drake enters the battlefield, it triggers twice, returning it and Great Whale from the battlefield to your hand.
9. Repeat.
10. If the seven lands can tap to produce at least 3, this combo nets infinite mana.