mamba
Legend
to me you are conflating two different things. Dolmenwood is a sandbox, a map with 100 linear predetermined locations / dungeons is a sandbox.Woah....so a more typical Sandbox does not have that much detail. Maybe the dm-player makes a map, but they sure are not making points of interest. Once the DM starts to create more then a small amount, the game slides down the slipper slope to being a Linear Game.
A more Sandbox game simply has a 'unknown cave' marked on it. And a player or two then say, and alter game reality, "there is a powerful magic sword in that cave we want", and the DM-player bows quickly to say "yes players".
The players saying ‘there is a cave beyond this forest and in it is a magical sword’ is something completely different
if the players go to the nearest inn and drink ale all day, the princess is not saved, no matter whether they did so ‘under the idea of saving the princess’ or notWhatever the players choose to do under the idea 'save the princess' becomes the game reality of saving the princess. The DM-player her has little or no power and simply makes what the players tell them to make and have the PCs save the princess.
Not sure what to call the game you describe here, nonsense seems to come to mind…