At a time when many federal agencies are in wholesale retreat from their missions (looking at you EPA), you've got to love the Federal Trade Commission.

Sure, a Republican may now be in charge, but the agency is still soldiering along, announcing on Monday that it will file suit in federal court to block a merger—the first such challenge of the Trump administration.

And what a merger. For once, it doesn't involve something like industrial switchboxes or vascular closure devices. The FTC is suing to block the merger of fantasy sports sites DraftKings and FanDuel.