'Sektor' 51 was suppose to be a adventure mode world until it was renamed to Endless Sektor 51. This world will be coming soon.
Although it hasn't been released yet it seems to be a large chemical lab with advanced technology. It is also shown that you can use jetpacks in this world in some locations. In the trailer, there are many obstacles that can be seen and is new, such as large gas cylinders, green toxic liquid, etc.