Skysphere size?

Simple question. How big is the skysphere, or, more specifically, is it possible for a player to, if I give them tools to teleport to any coordinates, escape the skysphere before they crash their computer due to how high the numbers are? Does the skysphere move with the player, or is it just one gigaaaaaaaaantic model that the rendering engine treats differently?

It’s just a static mesh. you can scale it bigger if you want. You can also script it to move with the player.
Either way, I think you shouldn’t give players the ability to teleport to any coordinate. You should validate that they’re still inside the world bounds and not under terrain etc.