This is partially for future reference, and partially for the moderators to evaluate. This is the list of answers that have been downvoted over the last day. I am writing it down here so that I don't forget them after the votes are automatically undone by the system for serial downvoting:
Including an image for reference:
Of those answers, only one is actually controversial (as H.Muster pointed out). I don't have the time or energy to fight anymore, this is a disruptive member, and I hope the moderators do something about it.
I think the person responsibile did a similar downvoting spree to Nick Stauner judging from chat comments.