Kixeye, a developer of social games on Facebook for core gamers, announced today that it has raised $18 million in its third round of funding led by Jafco Ventures.

While Zynga has become an incredibly profitable company by appealing to casual gamers, Kixeye focuses on attracting the kind of gamers that play hardcore PC and console games. Those Facebook users — mainly young males — play real time strategy games like Starcraft and console games like Call of Duty: Black Ops. They’re called “core gamers” because they play traditional video games like real-time strategy game Command and Conquer and role-playing games like those in the Final Fantasy series.

“In our kinds of games, you can engage and manipulate the battle, and you get total immersion in the game,” Kixeye chief executive Will Harbin told VentureBeat. “That’s something that resonates with core gamers, unlike other social gaming companies.”

It’s a strategy that has worked so far, with the company being profitable for more than 9 months, Harbin said. Some of Kixeye’s games include “synchronous play,” meaning the player is manipulating soldiers or ships in real time and telling them specifically where to shoot or patrol. Most social games on Facebook are “asynchronous,” meaning the users click a few buttons and the computer takes care of the rest of the game.

“We keep that piece in there, the core battling piece that makes RTS games so unique,” Harbin said. “And we also combine that with things that lend themselves to the virtual-goods model.”

That doesn’t mean Kixeye’s games don’t feature asynchronous play. For example, an opponent might not be on Facebook at the exact same time. So Kixeye’s games give players other things to do while they wait for opponents to respond, like exploring an open world in its Battle Pirates social game. Players can take over resource mines or encounter other new players while they wait for an opponent to make a move in a battle, Harbin said.

Kixeye’s games compete with Kabam, another social gaming company that says it focuses on core gamers. But saying you focus on core gamers and actually making games for core gamers are two very different things, Harbin said. He said Kabam actually copied and re-skinned Backyard Monsters, Kixeye’s first game that now boasts more than 1 million daily active users. Kabam said it has not copied that game.

Most of the new funding will be spent on buying additional servers and building out the back-end for the company’s games. It plans to release another real-time strategy game called War Commander soon, so the company is preparing the infrastructure for that game, Harbin said. Kixeye also wants to hire around 50 new employees before the end of the year, he said.

Kixeye has also added Andrew Trader, a veteran of the social gaming space and one of the founding members of Zynga, to its board of directors. Trader will help direct the company’s user acquisition and hiring, Harbin said.

“Effectively, [Trader] was responsible for two primary things at Zynga: people and user acquisition,” Harbin said. “Those are certainly super core to Zynga’s business in making them a multi-billion dollar company.”