Blue
Ravenous Bugblatter Beast of Traal
I've run in shared world campaigns, where it's the same world but multiple DMs. I have no problem with that.
I generally run homebrew setting, so unless I was starting at a high level it would be pretty hard but not impossible to justify someone coming into the game. I'd be willing to work with the player to do that. But that does mean that they will be disconnected from the history and unique features of this world and potentially a sense of alienation, which could be a fun plot/RP points or could be not-as-fun, so it would need to be talked over carefully. That said, I would want them to be recreated with the character creation rules I am using, so their ability scores, levels, equipments (or whatever for the game I'm using) match the power level of the other characters. My one caveat is that I ask for heroic or at least "good-adjacent" characters and usually want a Call to Adventure and connections to the world in backstory, so I would ask the player to craft a reason why they are willing to potentially lay down their life for this world.
I've got no beef with a character leaving the world to join another. If given a bit of warning I'll make the opportunity come up in play in their last session if it's something like moving.
All of that said, I'd prefer characters for the game I'm running. I greatly enjoy worldbuilding, start with broad strokes give players some authorial control over fleshing out around their characters and adding the details, and like working character connections into the story. I can still do character arcs without it, but a character arc to "get back to my friends in another world" is ultimately a "retire the character from this game" arc so I'd prefer something else.
EDIT: Just to add, I can't think of it coming up in more than a decade.
I generally run homebrew setting, so unless I was starting at a high level it would be pretty hard but not impossible to justify someone coming into the game. I'd be willing to work with the player to do that. But that does mean that they will be disconnected from the history and unique features of this world and potentially a sense of alienation, which could be a fun plot/RP points or could be not-as-fun, so it would need to be talked over carefully. That said, I would want them to be recreated with the character creation rules I am using, so their ability scores, levels, equipments (or whatever for the game I'm using) match the power level of the other characters. My one caveat is that I ask for heroic or at least "good-adjacent" characters and usually want a Call to Adventure and connections to the world in backstory, so I would ask the player to craft a reason why they are willing to potentially lay down their life for this world.
I've got no beef with a character leaving the world to join another. If given a bit of warning I'll make the opportunity come up in play in their last session if it's something like moving.
All of that said, I'd prefer characters for the game I'm running. I greatly enjoy worldbuilding, start with broad strokes give players some authorial control over fleshing out around their characters and adding the details, and like working character connections into the story. I can still do character arcs without it, but a character arc to "get back to my friends in another world" is ultimately a "retire the character from this game" arc so I'd prefer something else.
EDIT: Just to add, I can't think of it coming up in more than a decade.