That happens when it tried to load a resource file and the load failed, or the download failed.
If it has a repeated problem getting a file its best to restart the browser and maybe the computer to get a fresh start at loading the game.
I personally thought the final boss was lame. The looks for the boss that is a broken spaceship with electricity and wires all around would have looked better IMO.
Some people i saw were complaining about small cities, well beat the game (i did the city hall one) and then click city hall after the ending to leave for a new city. you will be able to Get a bigger city.
There are many sequals to the game, but they are all part of MC2. I think theres atleast 2. Burning Skies, and something else. The reason they are part of MC2 is because they relate to the MC2 storyline.
You know how in the loading screen and the credits how blood is splattered and stays on the objects? It would be epic to have an option to do that when blood hits something.
That happens when it tried to load a resource file and the load failed, or the download failed. If it has a repeated problem getting a file its best to restart the browser and maybe the computer to get a fresh start at loading the game.