Rule 614.13b

The same object can’t be chosen to change zones more than once when applying replacement effects that modify how one or more permanents enter the battlefield. Example: Jund (a plane card) says, “Whenever a player casts a black, red, or green creature spell, it gains devour 5.” A player controls Runeclaw Bear and casts Thunder-Thrash Elder, a red creature spell with devour 3. As Thunder-Thrash Elder enters the battlefield, its controller can choose to sacrifice Runeclaw Bear when applying the devour 3 effect or when applying the devour 5 effect, but not both. Thunder-Thrash Elder will enter the battlefield with zero, three, or five +1/+1 counters, depending on this choice.

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