Finishing this engagement certainly takes skill, but above all else, it takes truckloads of patience. One piece of cover might protect you from 9 shots in a row, but the tenth shot could still find a way through, ending your whole run and forcing you to start over. Being close to a shot on higher difficulties means instant death and the shots are random enough that finding cover is tricky. The real challenge here is avoiding the constant bombardment from the barge. After your 300th attempt, though, dispatching these foes will barely be an inconvenience. Judgments levels are built around a series of discrete levels separated by safe rooms where players can elect to apply certain modifiers to the upcoming. The barge stops occasionally to drop off enemies to fight which can be challenging on their own. While there is no way to target the barge directly, that won't stop the thing from harassing you for the entire fight. It is the hardest thing you'll do in the game, so that's good enough for us.
This encounter's status as a 'boss fight' will probably be disputed by some, but it features a recognizable primary threat The Barg.