Example: In Silent Hill 2 there are multiple endings for the game. Sometimes James leaves Silent Hill alone, Sometimes with Maria or laura and so on. One that stands out is the 'Rebirth' ending. James has fallen for the allure of the towns spiritual power after collecting arcane artefacts around the town -presumably left by the nameless Cult of the town- and has taken a row boat out to an Islet in Toluca Lake which the town surrounds on all sides to exact some ritual at what appears to be an old Abbey or Monastery.
The Islet is on the map, there is a dock on the landmass and something is calling James there but otherwise thats it. Its got no name. Its never referenced in the story again and outside of autists headcanon is never a part of the story beyond being on the map.
It feels like something they could always jump off too in a sequel -nowadays maybe pachishit- or autists could say its just the final area from SH3 but regardless its somewhere a dev added for a bit of mystique and intrigue for intrigues sake that never lead to anything but in its own way that just made people wonder about it.
What things like this spring to mind for you?