An FRC in-joke. People often ask (jokingly!) when FIRST robotics will create a game where the robots must act as submarines. The consensus is that a game with water on the field will never exist due to the obvious safety concerns it poses (well, there was that 1 game in like 1997... whew 1990s FRC was wild) but this has not stopped cries of "WATER GAME!" from being a decade-old (maybe older?) running joke.
In May 2024, FIRST revealed that the 2025 game would be called "Reefscape," leading to speculation that the fabled water game may finally turn from a dream to reality. Though the actual ruleset and field have not been revealed yet, many remain hopeful.
Personally, I think that Reefscape will merely be water-themed. The robots will probably have to do some sort of task that's themed around cleaning marine pollution in order to score points, and the game will not involve any real water. In any case, the actual rules of the game will be revealed in January 2025, so set your clocks. (Or not.)