Crackling Drake's power-setting ability is called a Characteristic Defining Ability. Because the Drake's CDA sets power and Volrath does not copy power, Volrath will not copy the Drake's CDA.
706.9d When applying a copy effect that doesn’t copy a certain characteristic, retains an original value for a certain characteristic, or modifies the final value of 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.
Two Score, Minus Two or: A Stargate Tail
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