Does it have to be a human though? The power output on a siongle wight seems to be large enough, so maybe we don’t really need a human. What if the night King made something smaller, say wight raccoons? you could probably make a decent flat-four using four of those, and stick them underneath the chassis, Tesla Battery…

Also, if he gets mad at you, just tell him your mother’s name is Martha. And then he’ll instantly forgive you.