Rule 201.4a

If an ability’s effect grants another ability to an object, and that second ability refers to that first ability’s source by name, the name refers only to the specific object that is that first ability’s source, not to any other object with the same name. This is also true if the second ability is copied onto a new object. Example: Gutter Grime has an ability that reads “Whenever a nontoken creature you control dies, put a slime counter on Gutter Grime, then create a green Ooze creature token with ‘This creature’s power and toughness are each equal to the number of slime counters on Gutter Grime.’” The ability granted to the token only looks at the Gutter Grime that created the token, not at any other Gutter Grime on the battlefield. A copy of that token would also have an ability that referred only to the Gutter Grime that created the original token.

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