Is Shadow of the Second Sun legal in Standard, Modern, and Commander?

Shadow of the Second Sun is legal in: Modern, Legacy, Vintage, Commander, Historic.

Shadow of the Second Sun

Q: What type of card is Shadow of the Second Sun?

Shadow of the Second Sun is an Enchantment — Aura. Its oracle text reads: "Enchant player At the beginning of each of enchanted player's postcombat main phases, there is an additional beginning phase after this phase. (The end step happens after the added untap, upkeep, and draw steps.) *Live fully, then return to the beginning.*"

Enchantment — Aura

Enchant player

At the beginning of each of enchanted player's postcombat main phases, there is an additional beginning phase after this phase. (The end step happens after the added untap, upkeep, and draw steps.)

*Live fully, then return to the beginning.*

Set Modern Horizons 3

Rarity Mythic Rare

Mana Value 6

Artist Danny Schwartz

Collector # 70

Scryfall