Gamasutra's Stanislay Costuic writes: "Creating and filling open worlds is a tricky thing. On one hand, you want them to be massive, expansive, provide a feeling that you have a whole sandbox to play in, and incentivize exploration. On the other hand, you also don’t want them to feel like there’s nothing to do, you want there to be content. Pretty much every open world game (that is not an RPG, I suppose) tries to mitigate this issue by adding a bunch of collectibles spread all over the world. That’s content that, if the player chooses to complete it, will have them explore every part of the map. But, to be honest, I consider most collectibles to be filler with very little value. What’s much more important is how the world is utilized in missions or other meaty actual content. And a game that I think is a very good example of open world usage in missions is Assassin’s Creed II."