Card name

Mox Opal

Mana cost

{0}

Mana value

0

Type

Legendary Artifact

Rarity

mythic

Set

Double Masters (2XM)

Collector number

275

Artist

Volkan Baǵa

Official rulings

2020-08-07 If you control Mox Opal and one other artifact, then have a second Mox Opal enter the battlefield as your third artifact, you can't activate either one's mana ability before putting one into your graveyard due to the “legend rule.”