Humanity is besieged by hordes of Mental, who are sweeping the world, ravaging what remains of a shattered and defeated civilization. The last resistance to the invasion is put up by the Earth Defense Force, whose vanguard is Sam "Serious" Stone and his heavily armed squad of specific commandos. Croteam returns in a turbocharged prequel to the Serious Sam series, which takes the mayhem to unprecedented levels. The classic Serious Sam formula has been rebuilt, and players will be given an unstoppable arsenal and will have to fight battles against an incredible number of enemies. You have to take steps to the side, circle your opponents, and quickly retreat from nightmarishly difficult situations. RAIDER HORDESThe ultimate cast of space invaders is back with some buffs! Fight an incredible number of Mental's minions, such as the iconic headless kamikaze, headless rocket launcher, kleer, foldable, bull or khnum! Face all-new enemies and giant monsters such as the wild processed, the hideous Blabber, the mighty Zealot, and more. EXPLOSIVE ARSENALWhen you can wield devastating weapons and choose tools for any situation. Take down hordes of Mental with a powerful double-barreled shotgun, a minigun that scolds enemies, a powerful chainsaw launcher, an all-new shotgun, and the iconic cannon. Upgrade your toys and enjoy the violent beauty of the Targeted Rocket Launcher and the powerful laser death beam. CO-OP CHAOSThe action-packed campaign with your friends in four-player online co-op mode! Challenge yourself and take on exciting main missions and thrilling side quests on modified difficulties. LEGIONUS SYSTEMTerious Sam 4 recreates the most exciting moments in the franchise's history with a new legion system that swarms the battlefields with thousands of enemies!