Imagine an open-world in the country fields. Or, why not, you can have flying islands like in Zelda Skyward Sword, where the boundary is given by not-falling-to-death.ģ) challenging who tries: you can always increase the challenge exponentially as far as the player goes. If the city was invaded by aliens, maybe the gigantic spaceship is itself blocking the path to other parts of the city as it crushed when arriving. A huge fire destroying parts of a city, or a gas leak, or a radiation accident in part of a city that blocks the way. A part of a city with too many buildings in the way and the only possible streets blocked. A dense forest, as someone else told here. Then, if he/she can swim, it becomes again a problem of just letting him/her swim forever.Ģ) scene barrier: it does not have to be mountains.

Of course, if you have modern boats, ships, jet-skis, etc, and the concept of gas as resource, that works well too and then it becomes part of the item number 4 below, since the player can just sail until running out of gas. The player would just get tired at some point of going forward and then would decide to reload (because going back all over again would be just as tedious). That alone would closer resemble the idea of how distant it would be in real life to cross an ocean by swimming. Just let him/her swim infinitely (like with a proceduraly generated infinite ocean). Just some quick additional suggestions, that sometimes complement what others have already said.ġ) water solution: I never understood why killing the player with a shark or something.

Warcraft 3 world editor shallow water