Go-Shintai of Life's Origin + There and Back Again + Clock of Omens + Contagion Engine + Encroaching Mycosynth
Go-Shintai of Life's Origin
There and Back Again
Clock of Omens
Contagion Engine
Encroaching Mycosynth
Infinite artifact ETBInfinite artifact LTBInfinite artifact sacrifice triggersInfinite artifact tokensInfinite colored manaInfinite death triggersInfinite creature ETBInfinite creature LTBInfinite proliferateInfinite Treasure tokensPut all Mountains from your library onto the battlefieldInfinite mana nonland permanents you control can produceInfinite untap of nonland permanents you control
How it works
At the beginning of your precombat main phase, There and Back Again triggers, putting a lore counter on it.
There and Back Again's third chapter ability triggers, creating a legendary 6/6 Smaug creature token and causing you to sacrifice There and Back Again.
If you control two Smaugs, put one into your graveyard due to the legend rule.
If you do, the Smaug that died triggers, creating fourteen Treasure tokens.
If you made Treasures this way, activate nine Treasures by tapping and sacrificing them, adding 4.
Activate Go-Shintai by paying and tapping it, returning There and Back Again from your graveyard to the battlefield with a lore counter on it.
There and Back Again's first chapter ability triggers, causing the Ring to tempt you.
Activate Contagion Engine by paying 4 and tapping it, putting two lore counters on There and Back Again.
There and Back Again's second and third chapter abilities trigger.
Holding priority, activate Clock of Omens twice by tapping four artifacts, untapping Contagion Engine and Go-Shintai.
Resolve the second There and Back Again trigger, causing you to search your library for a Mountain and put it onto the battlefield.
Resolve the third There and Back Again trigger, creating a legendary 6/6 Smaug creature token and causing you to sacrifice There and Back Again.