On May 1st, Activision and Treyarch officially announced Call of Duty: Black Ops 2, confirming the follow up to 2010's first person shooter that fans were expecting. With the unveil came a lot of hype about the game's setting, but attention has now shifted to demand for an upgraded engine.

Activision has been putting out a new Call of Duty release every year since the original debuted, and some players may be getting tired of the recycled graphics engine. However, according to Kotaku, head of Treyarch Mark Lamia said he acknowledges this but ensured gamers that they might not see a fresh overhaul in the technology used for Black Ops 2.

Engines, each time they get touched, they change, he said to Activision blogger Dan Amrich, Kotaku reports. The creators alter them; they don't modify what they don't need to and then they alter what they need to. You can't make a competitive product if you're not upgrading that engine along the way.

Lamia went on to specify that graphics and lighting are the gameplay elements that receive retouching.

I think what people are asking for is for us to push, he said. They want us to make a better-looking game; they want things. I don't think those are things that people can't ask for.

The Treyarch executive acknowledged that fan concerns are valid, but a completely new engine may not be the solution.

I think the questions are valid, he said. The answer may not need to be an entirely new engine, but you might need to do an entire overhaul of your entire lighting system. The trick is, we're not willing to do that if we can't keep it running at 60 frames per second-but we did that this time. So this is the 'Black Ops II' engine.

The engine used in the previous Black Ops release and games such as Call of Duty: Modern Warfare, Call of Duty: World at War, Quantum of Solace, and Call of Duty: Modern Warfare 2 is the IW Engine. This is developed by Infinity Ward and ran off the previous id Tech 3 engine until the company built its own in-house middleware.

If you've played that game [Modern Warfare 2], then the quality of the engine and the experience it can deliver needs no introduction, wrote Chris Stead of IGN. Phenomenal animations and lighting lead the way, although its ability to handle complex AI, amazing sounds, depth of field and dynamic bullet penetration-all at a blistering pace-cannot be ignored.

But for some hardcore gamers, gameplay should always take precedence over graphics and engines. And this means an emphasis on Zombie Mode is a crucial part of the Black Ops sequel's success.

What we loved about zombies is how you have to work so closely together to survive, which brings some really intense gameplay and great memories with family, friends, and strangers, writes Daniel Chubb of In Entertainment. Treyarch has given their team plenty of room for creating the next zombie mode, which doesn't need to follow the main theme of 'Black Ops 2' and we cannot wait to see where it takes us.

Two days after the global unveil of Black Ops 2 artwork teasing the new Zombie Mode was launched, enticing fans to gear up for the next Call of Duty installment. The Zombie Mode to be found in Black Ops 2 is said to be an entirely new game, according to VentureBeat. Lamia also insisted that fans are going to be pleased with the upcoming undead developments.

If you like zombies, you're going to be really happy with what we're doing with 'Black Ops 2,' he said in an episode of Roll Call on Call of Duty Elite TV. It's our biggest, most ambitious zombies yet.

However, for those eagerly anticipating the new Zombie Mode, there may be a tiny sneak peak in store. A screenshot from the gameplay mode leaked on to an Activision community forum on May 7th. It doesn't show too much, but it gives some insight into the setting and graphics involved.

It is unclear whether or not the image is credible since there has been no confirmation, but it comes from a source that has claimed to have received an early copy of Black Ops 2.

Call of Duty: Black Ops 2 will be available on Nov. 13th and will be set in war-torn Los Angeles in the year 2025.

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