It seems that at one point the Combat Zone in Fallout 4 had more content than what was included the game upon release.
The video from Kotaku above takes a look at some interesting, unused audio clips found in the game files.
These clips were created for Combat Zone ring announcer Tommy Lonegan, which suggests the player would at one time have entered the ring to fight with their fists for caps. The harder the fight, the bigger the pay and the payout would grow larger as the player went up in rank.
This may be added in later down the road through DLC, but at this point we’re just speculating. If it never happens, there’s always the modding community.
Also shown in the video is a look at the ocean floor of the game along the harpoon gun which was found by a modder in the game files. It’s speculated the weapon’s code was a leftover from the 20 Leagues Under the Sea quest which was cut from the core game.
As Patricia notes in the video, sometimes content gets cut so a developer can ship a game, so it’s quite possible Bethesda will flesh out Fallout 4’s Combat Zone more in the future – and give us something to do under the sea.