Even when PopCap is doing a zombie game, the developer-publisher studio has a way of adding an air of adorable charm to its products. However, the casual-gaming powerhouse appears to be looking to push the envelope in the future, announcing today the formation of a new, "edgier" label called 4th & Battery.

　　Kids, you might want to look away for this. The new label will be focused on projects with a smaller scope and scale, as well as arcade-style gameplay. PopCap said that 4th & Battery's primary platforms will be PC, Facebook, and iPhone, and that some of the projects released from this label will fall squarely in the M-for-Mature rating bracket.

　　"4th & Battery is a purely experimental, creative label with none of the typical concerns like schedules, profitability, or even target audience," PopCap cofounder and chief creative officer Jason Kapalka said of the new division. "It's kind of the video game equivalent of B-sides or short films. Expect weirdness."

　　That "weirdness," not to mention M-rating, will be on display in 4th & Battery's first effort, Unpleasant Horse. The game sees players assuming the role of an evil, winged horse that takes its pleasure (and earns points) by "destroying small birds." The titular Unpleasant Horse also seeks to clip the wings of other Pegasus-like creatures so they fall from the sky and into the "perpetual meat grinder" that is the ground.

　　PopCap expects to release Unpleasant Horse for the iPhone and iPod touch later this month. The game will be free of charge.