Cast Blue Sun's Twilight by paying {5}{U}{U}, targeting a creature.
Holding priority, cast Dualcaster Mage by paying {1}{R}{R}.
When Dualcaster Mage enters the battlefield, it triggers, copying Blue Sun's Twilight, targeting Dualcaster Mage.
Resolve the copy of Blue Sun's Twilight, creating a token copy of Dualcaster Mage.
Repeat from step 3.

Infinite creature tokens

Infinite ETB

Infinite magecraft triggers

Dualcaster Mage

Blue Sun's Twilight

Cast Blue Sun's Twilight by paying {5}{U}{U}, targeting a creature.
Holding priority, cast Naru Meha either from your hand or from the command zone by paying {2}{U}{U} plus commander tax, if applicable.
When Naru Meha enters the battlefield, it triggers, copying Blue Sun's Twilight, targeting Naru Meha.
Resolve the copy of Blue Sun's Twilight, creating a token copy of Naru Meha.
Put either Naru Meha into your graveyard due to the legend rule.
Repeat from step 3.

Infinite death triggers

Infinite LTB

Naru Meha, Master Wizard

Cast Blue Sun's Twilight by paying {5}{U}{U}, creating a token copy of Mirror-Mad Phantasm.
Activate the Mirror-Mad Phantasm token by paying {1}{U}, shuffling the token into your library and milling your entire library due to it not having a card named Mirror-Mad Phantasm in it.

Infinite self-mill

Mirror-Mad Phantasm

Cast Mnemonic Deluge by paying {6}{U}{U}{U}, exiling Blue Sun's Twilight and casting three copies of it without paying their mana costs.
Resolve the three Blue Sun's Twilight copies, creating three token copies of Biovisionary.
At the beginning of your end step, each Biovisionary you control triggers.
Resolve the first trigger, causing you to win the game.

Win the game

Biovisionary

Mnemonic Deluge

Cast Blue Sun's Twilight by paying its mana cost, targeting Biovisionary.
Holding priority, activate Echo Mage by tapping it, copying Blue Sun's Twilight twice, with both copies targeting Biovisionary.
Resolve all Blue Sun's Twilight spells, creating three token copies of Biovisionary.
At the beginning of your end step, each Biovisionary triggers. Resolve the first trigger, causing you to win the game.

Echo Mage

Activate Thunderclap Drake by paying {2}{U} and sacrificing it.
Cast Blue Sun's Twilight by paying {5}{U}{U}, targeting Biovisionary.
Thunderclap Drake triggers, copying Blue Sun's Twilight at least twice, with all copies targeting Biovisionary.
Resolve all Blue Sun's Twilight spells, creating at least three copies of Biovisionary.
At the beginning of your end step, each Biovisionary triggers, causing you to win the game.

Thunderclap Drake

At the beginning of your precombat main phase. Summon: G.F. Cerberus triggers, putting a lore counter on it and triggering its third chapter ability, copying the next instant or sorcery spell you cast twice.
Cast Blue Sun's Twilight by paying {5}{U}{U}, targeting Biovisionary.
Summon: G.F. Cerberus triggers, copying Blue Sun's Twilight twice, with the copies targeting Biovisionary.
Resolve all Blue Sun's Twilights, copying Biovisionary three times.
At the beginning of your end step, each Biovisionary triggers. Resolve the first trigger, causing you to win the game.

Summon: G.F. Cerberus

Cast Blue Sun's Twilight by paying {5}{U}{U}, creating a token copy of Bellowing Aegisaur.
Activate a mana-producing permanent you control by tapping it, adding at least {G}.
Activate Wayta by paying {G} and tapping it, causing Cacophodon and the nontoken Bellowing Aegisaur to fight each other, with each only taking 1 damage due to Temple Altisaur.
Cacophodon and Bellowing Aegisaur each trigger twice.
Resolve all Bellowing Aegisaur triggers, putting two +1/+1 counters on each other creature you control.
Resolve both Cacophodon triggers, untapping the mana-producing permanent and Wayta.
Repeat from step 2, alternating between having the token and nontoken Bellowing Aegisaur fight Cacophodon.

Combos with "Blue Sun's Twilight"