Opal Acrolith

Enchantment    (CMC:3)

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. : Opal Acrolith becomes an enchantment.

22 UZ • ENRobh Ruppel

™ & © 1993—1998 Wizards of the Coast

Legal in: Urza Block,Legacy,Vintage,Commander

Oracle Text (click to copy):

Opal Acrolith {2}{W} Enchantment Whenever an opponent casts a creature spell, if Opal Acrolith is an enchantment, Opal Acrolith becomes a 2/4 Soldier creature. {0}: Opal Acrolith becomes an enchantment.

---

View this MTG card on Gatherer

10/4/2004
When it turns into an enchantment, it is no longer a creature.
10/4/2004
Changes into a creature even if the spell is countered.
10/4/2004
When it turns into a creature, it is no longer an enchantment.
10/4/2004
It triggers when the spell is cast, which means it becomes a creature before that spell resolves.
4/1/2008
A "creature spell" is any spell with the type Creature, even if it has other types such as Artifact or Enchantment. Older cards of type Summon are also Creature spells.
8/1/2008
A noncreature permanent that turns into a creature can attack, and its  abilities can be activated, only if its controller has continuously controlled that permanent since the beginning of his or her most recent turn. It doesn't matter how long the permanent has been a creature.

---

Card Opal Acrolith is not on TCGPlayer.