Homefront: The Revolution has been revealed by publisher Deep Silver.

Helmed by a new development team at Crytek UK, the sequel is set four years after the original Homefront, focusing on a resistance movement in Philadelphia after the United States has become occupied by a foreign alliance.

Moving away from a linear sequence of missions to a more free-roaming city to explore - akin to previous Crytek games such as Far Cry and Crysis - players must plan and execute guerrilla warfare.

As the resistance grows in strength, you'll gain access to more resources and city districts, leading to visible change for the city and its residents.

"One of the main differentiators I think with other games is our game world evolves over time... you'll see more acts of resistance from civilians, you'll see protests occur," producer Dave Stanton told Digital Spy.

"That extends all the way up to full on revolution on the streets that plays out – it's very much an evolving game world from start to finish."

Philadelphia was chosen because of its history as the birthplace of the American Revolution, which the invading Korean Republic forces have now made their capital in the occupied United States.

"Philadelphia gives us a lot; if gives us that history, it makes sense for the fiction, in it's a symbol of the KPA's complete domination of the United States, and it makes sense for the story," Stanton explained.

"If there ever was going to be a city, if the KPA had chosen this city of their sign of their complete domination, it's a really a city you'd expect revolution to occur.

"It's the birthplace of independence originally, and it makes sense that it's going to be the birthplace of a second war of independence, as it were."

Philadelphia's districts has been augmented with dystopian structures, such as watch towers and walkways, as well as regular patrolling guards and flying drones.

Huge television screens, meanwhile, broadcast propaganda to the oppressed citizens throughout the game's day and night cycle.

The resistance fights back against the regime using "asymmetric" guerrilla warfare, where ambushes, assassinations and weapons crafted from scavenged items are used to level the playing field against the KNP's advanced arsenal of drones and high-tech machinery.

Items can be combined together in a variety of ways. For example, the player can strap an improvised explosive device onto an RC car, and drive it to an outpost to create a distraction as part of a larger attack.

As well as a single-player, free-roaming story, a separate four-player co-operative experience set within the same areas of the city allow players to work together to pull off co-ordinated attacks.

Coming to Xbox One, PS4, PC, Mac and Linux, the team at Crytek UK – formally TimeSplitters team Free Radical Design - is using a "bleeding edge" version of the CryEngine to achieve its dystopian vision.

"We've got an R&D team in Nottingham that work on some of the features of CryEngine – so we're constantly taking new drops from the tech team," Stanton explained.

"They're responsible for the streaming technology to create that free-roam environment, they're responsible for the real-time day and night and weather cycles and dynamic clouds and all those kind of things.

"As a result of that we're on the absolute, bleeding edge with CryEngine."

Homefront: The Revolution will be available sometime in 2015.