Named after the Seattle, Washington intersection where PopCap’s Seattle headquarters are located, 4th & Battery today introduced its first game, Unpleasant Horse.

“4th & Battery is a pressure valve intended to keep our heads from exploding,” explained Ed Allard, Executive Vice President of Studios at PopCap. “The PopCap brand has become closely associated with ultra-high quality, polish and attention to detail — which is a great thing. But our standard game development process is therefore long and involved, and doesn’t really accommodate all of the creativity pumping through our collective veins. 4th & Battery gives us a way to quickly try really strange or marginal ideas, and to give our designers a safe area to hone their chops.”

4th & Battery is expected to produce several games per year, primarily small-scale, arcade-style games for platforms ranging from PC to Facebook and iPhone. Unlike PopCap’s traditional franchises, some of the content emanating from 4th & Battery, including its initial launch title Unpleasant Horse, will be aimed at mature audiences.

“4th & Battery is a purely experimental, creative label with none of the typical concerns like schedules, profitability, or even target audience. It’s kind of the video game equivalent of B-sides or short films,” explained Jason Kapalka, co-founder and Chief Creative Officer at PopCap. “Expect weirdness.”

The first game from 4th & Battery, Unpleasant Horse, was announced today. Players take on the role of – wait for it! – a strikingly unpleasant horse that sports wings and advances through the game by destroying small birds and landing on more pleasant horses from above. Landing atop other horses enables the player to force them earthward into a perpetual meat grinder for extra points and special bonuses. Available later this month for the iPhone and iPod touch through the Apple App Store, Unpleasant Horse will be available for free.