Is Mirrodin Besieged legal in Standard, Modern, and Commander?

Mirrodin Besieged is legal in: Modern, Legacy, Vintage, Commander.

Mirrodin Besieged

Q: What type of card is Mirrodin Besieged?

Mirrodin Besieged is an Enchantment. Its oracle text reads: "As this enchantment enters, choose Mirran or Phyrexian. • Mirran — Whenever you cast an artifact spell, create a 1/1 colorless Myr artifact creature token. • Phyrexian — At the beginning of your end step, draw a card, then discard a card. Then if there are fifteen or more artifact cards in your graveyard, target opponent loses the game."

Enchantment

As this enchantment enters, choose Mirran or Phyrexian.

• Mirran — Whenever you cast an artifact spell, create a 1/1 colorless Myr artifact creature token.

• Phyrexian — At the beginning of your end step, draw a card, then discard a card. Then if there are fifteen or more artifact cards in your graveyard, target opponent loses the game.

Set Modern Horizons

Rarity Rare

Mana Value 3

Artist Bram Sels

Collector # 57

Scryfall Gatherer