Livio, Oathsworn Sentinel + Great Whale + Great Oak Guardian
Livio, Oathsworn Sentinel
Great Whale
Great Oak Guardian
Infinite blinkingInfinite creature ETBInfinite creature LTBInfinite mana creatures you control can produceInfinite mana lands you control can produceInfinite untap of creatures you controlInfinitely large creatures you control until end of turn
How it works
Activate up to seven mana-producing lands by tapping them, adding at least 5.
Activate Livio's first ability twice by paying 2, exiling Great Whale and Great Oak Guardian with aegis counters on them.
Activate Livio's second ability by paying 2 and tapping it, returning Great Whale and Great Oak Guardian from exile to the battlefield.
Great Oak Guardian and Great Whale enter the battlefield, triggering their abilities.
Resolve the Great Whale trigger, untapping up to seven lands you control.
Resolve the Great Oak Guardian trigger, untapping each creature you control and giving them +2/+2 until end of turn.