After I got Saltzpyre’s room I noticed there was a locked door with blood leading to it; I imagined maybe it’d open up if I continued leveling up and that maybe all other characters get room upgrades as they level up too. I later on found out that this is not the case but think it would be a nice addition considering how much empty space is in the keep.
All characters have a room. but they are open randomly. for example Sometimes the room from sienna is open and sometimes its locked
they open if you reach level 10 with the Character. They do not open randomly afaik.
It might appear that way if you join games hosted by other people. They might have different characters on Level 10 and so different Rooms unlocked.
The rooms are not randomly open. Once you reach level 10 with a character, their room will be permanently open in your lobby. So if you go to the lobby of someone who hasn’t reached level 10 with your character, you will not see their room.