Rule 707.4

Some effects cause a permanent that’s copying a permanent to copy a different object while remaining on the battlefield. The change doesn’t trigger enters-the-battlefield or leaves-the-battlefield abilities. This also doesn’t change any noncopy effects presently affecting the permanent. Example: Unstable Shapeshifter reads, “Whenever a creature enters, Unstable Shapeshifter becomes a copy of that creature and gains this ability.” It’s affected by Giant Growth, which reads “Target creature gets +3/+3 until end of turn.” If a creature enters the battlefield later this turn, Unstable Shapeshifter will become a copy of that creature, but it will still get +3/+3 from the Giant Growth.

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