The XM29 OICW (Objective Individual Combat Weapon) was a highly ambitious, futuristic assault rifle system developed for the U.S. Army in the late 1990s and early 2000s. It was essentially a "two-in-one" weapon designed to replace both the M16 rifle and the M203 grenade launcher with a single, high-tech platform. While it looked like something straight out of a sci-fi movie (and famously appeared in games like Half-Life 2), it never saw mass production