Adding some ideas for ways this could be done (with moving map):

Game starts with multiple large circles that shrink down and then moves and shrinks over time. The circles will move randomly along some path that gets them closer to each other. When the circles meet, they merge together. Players can see their section of the map + a navigation panel indicating their location and other players / boxes. As boxes tend to generate closer to the circle as the game goes on, it’ll hopefully force players to get closer and closer until there’s one circle left