A build of Call of Duty: Black Ops 2 leaked out onto the web last week. The folks at Treyarch got in touch with us to say that contrary to the leaker's claim that the leak belonged to the 'retail version', it was in fact a demo build, which the developer had used for testing.

Despite the apparent lack of content in the demo build, the files contained within it have been reported to reference content players can expect to see in the retail version once it's out.

Folks from the se7ensins forums, who've had a chance to tamper with the files, posted that Black Ops 2's new Zombies mode contains a variety of mutations, or modes, to provide some variation in gameplay.

These include:

– Classic

– Survival

– Race

– Meat

– No Man’s Land

– Turned

– Returned

– Grief

It's unclear whether all of the names refer to game modes, or if some of them refer to specific maps in Zombies Mode.

In addition to the possible modes in Zombies Mode, the folks on the forum report that the regular multiplayer version of Black Ops 2 contain the following maps, and describe them as follows:

Carrier – Chinese Supercarrier. Open engagements on the deck, with great close quarter fights through the hull.

Cargo – Port of Singapore. Good for close quarters engagements and verticality.

Drone – Hidden drone facility in the heart of the Mynamar jungles. Great long engagements down the center, fun close quarter fights through the facility.

Express – Los Angeles bullet train station. Good long to medium engagements up and down the bullet train tracks.

Hijacked – Luxurious super yacht. Frantic, yet controlled close quarters engagements.

Aftermath – Set in a ruined downtown Los Angeles after an invasion.

Meltdown – Pakistan nuclear power plant. Battle for control of the nuclear cooling tower and the surrounding facilities.

Nightclub – Floating resort in the middle of the Indian Ocean. Tight corners and angles throughout.

Overflow – Peshawar, Pakistan. Great urban engagements in the flooded streets.

Raid – Fight through this hillside mansion, in the Hollywood Hills. Hectic close quarters engagements.

Slums – Run down section of Panama. Great close quarters engagements and tough chokes to fight over.

Socotra – Urban streets of Yemen. Tight alleys and close quarters engagements.

Turbine – Wind farm in the steep hills of Yemen. Fight across the different tiers and angles.

Village – Originally Yemen

As with all the previous leaks for Black Ops 2, I'd suggest taking this in with a pinch of salt and assume that nothing you see here is final.

Call of Duty: Black Ops 2 is set for release on November 13 for the PC, Xbox 360 and PlayStation 3.