Rule 707.9d

When applying a copy effect that doesn’t copy a certain characteristic, retains one or more original values for a certain characteristic, or provides a specific set of values for a certain characteristic, any characteristic-defining ability (see rule 604.3) of the object being copied that defines that characteristic is not copied. If that characteristic is color, any color indicator (see rule 204) of that object is also not copied. This rule does not apply to copy effects with exceptions that state the object is a certain card type, supertype, and/or subtype “in addition to its other types.” In those cases, any characteristic-defining ability that defines card type, supertype, and/or subtype is copied. Example: Quicksilver Gargantuan is a creature that reads, “You may have Quicksilver Gargantuan enter the battlefield as a copy of any creature on the battlefield, except it’s 7/7.” Quicksilver Gargantuan enters the battlefield as a copy of Tarmogoyf, which has a characteristic-defining ability that defines its power and toughness. Quicksilver Gargantuan does not have that ability. It will be 7/7. Example: Glasspool Mimic is a creature that reads “You may have Glasspool Mimic enter the battlefield as a copy of a creature you control, except it’s a Shapeshifter Rogue in addition to its other types.” Glasspool Mimic enters the battlefield as a copy of a creature with changeling. Glasspool Mimic will have changeling and will have all creature types.

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