Whenever one of your opponents successfully casts a creature spell, if Opal Acrolith is an enchantment, Opal Acrolith becomes a 2/4 creature that counts as a Guardian. {0}: Opal Acrolith becomes an enchantment.

• Number: 22
• Rarity: U
• Type: Enchantment
• Mana cost: 2W
• Color: White
• Artist: Robh Ruppel