This is a great game for large groups/summer camps. I found it on a YouTube video by coach Rob Carvajal Jr. It is part of an adult format he uses that is similar to a boot camp or cardio class, lots of fitness components plus some live ball play. The live ball format is where we get to the 42.
42 is basically a variation on King of the Court where one player or team is designated the champ and all others are challengers. In Coach Rob's version, the challenger must earn 4 points before the champs earn 2 points. If they do so, they are the new champs. Coach feeds first ball to challengers, then live play proceeds. Since the players may take a while to get their 4 points, the fitness stations come in handy to keep the other players busy while they are waiting to play in.