Finifugal Games is excited to announce that their upcoming genre-blending real time strategy game Colony Siege is launching on Early Access on Steam this summer. Players will have to build walls, turrets and mobile armies to defend against two wildly different factions of invaders, each requiring very different strategies to overcome. Take a peek at the enormous enemy swarms in the trailer below.

Over the course of a 23-mission branching campaign, players will unlock new technologies, units and upgrades in order to turn the alien tide, as well as uncover gruelling Survival and Endless challenges for each map. With the odds stacked against them, players can recruit a buddy and tackle the entire game in online co-op, or face down the 44 enemy types solo.

Unlike most tower defense games, Colony Siege allows players to build their fortifications and traps almost anywhere on the battlefield. Walls can be used to funnel enemies into kill-zones and mobile units controlled in traditional RTS fashion can intercept more aggressive foes. It’s a fresh challenge for fans of both regular strategy games and more structured tower defense.

Colony Siege launches onto Steam Early Access this Summer for $19.95, with a final release planned for later this year. Dates will be announced soon.