Infinite creature LTBInfinite creature ETBInfinite colored manaInfinite creature sacrifice triggersInfinite death triggersInfinite untap of creaturesInfinite mana creatures you control can produce
How it works
During your precombat main phase, activate Phyrexian Altar by sacrificing the additional nontoken green creature, adding one mana of any color.
When the creature dies, Verdant Succession triggers.
Holding priority, activate Hua Tuo by tapping it, putting the creature from your graveyard onto the top of your library.
Resolve the Verdant Succession trigger, searching your library for the sacrificed creature and putting it onto the battlefield.
When the creature enters the battlefield, Intruder Alarm triggers, untapping all creatures.
Repeat.
This intricate loop turns the cycle of life and death into a perpetual motion machine, fueled entirely by the graveyard and the battlefield. When you sacrifice a green creature to Phyrexian Altar, **Verdant Succession** immediately steps in to fish a replacement straight out of your library, while **Hua Tuo, Honored Physician** quietly tucks the original card right back onto the top of your deck just in time. Every time that fresh copy arrives, **Intruder Alarm** triggers its global untap effect, keeping **Hua Tuo, Honored Physician** ready to tap again and netting you an extra mana with every iteration.