The Combine ( ) is a fictional multidimensional empire which serves as the primary antagonistic force in the 2004 video game Half-Life 2, and the subsequent episodes developed by Valve. The Combine consist of organic, synthetic, and heavily mechanized elements. They are encountered throughout Half-Life 2 and its episodic sequels, as well as Half-Life: Alyx, as hostile non-player characters as the player progresses through the games in an effort to overthrow the Combine occupation of Earth. The Combine are frequently shown as cruel rulers over the citizens of Earth, suppressing dissent with brutality, policing using violence and/or using invasive surgery to transform humans into slaves. Throughout the games, the player primarily battles transformed humans as well as synthetic and mechanical enemies that are the product of Combine technology. In addition to their role within the Half-Life series, the Combine have been adapted for machinima productions and one Combine character type has been made into plush toys by Valve. Design Certain elements of the Combine's appearance, such as that of the Advisor, are inspired by the works of Frank Herbert. The towering Striders seen throughout Half-Life 2 and its subsequent episodes are based directly on the Martian tripods of the H.G. Wells novel The War of the Worlds, where said Martians invade Victorian England, using the tripods as their main "weapon". The name "Combine" itself is a tribute to Ken Kesey's novel One Flew Over the Cuckoo's Nest, which features a collection of authorities which mechanistically manipulate and process individuals. During Half-Life 2s development, various concepts for Combine non-player characters were cut. Female Combine Assassins, similar to black ops Assassins featured in the first game, were planned but later abandoned, although they appear in the Half-Life 2: Survivor arcade game. Another non-player character, the Cremator, was conceptualized as a Combine laborer who cleaned the streets of bodies after a battle with an acid gun and although removed from the game, its head was featured on a desk in Eli Vance's laboratory in Black Mesa East. Other cuts included a variety of alien Combine soldiers that would have complemented the trans-human soldiers in the game and a number of synthetic combat machines. Many of Half-Life 2s Combine characters went through multiple redesigns; the Combine Overwatch soldier was subjected to at least twelve redesigns before the final appearance was settled on. Actress Ellen McLain provides the voice for the Combine Overwatch announcer and