This game needs the Unity Web Player plug-in, if after a while the game doesn't load... you have to download and install this plug-in, it's also recommended that you restart all the pages on your web search engine after installing (especially if you use Internet Explorer)
Click on the unity logo and follow the instructions the owners of the plug-in give you to download and install the plug-in.
One of the most popular sandbox and role-playing games lately is "Minecraft", and here we have an awesome clone completely in 3D. Survive in a world full of life or get creative in the open world mode. Remember that you need the Unity 3D plugin to play.