Can be activated in:
Åland Islands, Albania, Algeria, Andorra, Angola, Anguilla, Antarctica, Antigua and Barbuda, Argentina, Armenia, Aruba, Australia, Austria, Azerbaijan, Bahrain, Bangladesh, Barbados, Belarus, Belgium, Belize, Benin, Bermuda, Bhutan, Bolivia, plurinational state of, Bonaire, Sint Eustatius and Saba, Bosnia and Herzegovina, Bouvet Island, Brazil, British Indian Ocean Territory, Brunei Darussalam, Bulgaria, Burkina Faso, Burma, Burundi, Cambodia, Cameroon, Canada, Cape Verde, Cayman Islands, Central African Republic, Chad, Chile, China, Christmas Island, Cocos (Keeling) Islands, Colombia, Comoros, Congo, Congo, Democratic Republic of the, Cook Islands, Costa Rica, Cote d'Ivoire, Croatia, Cuba, Curaçao, Cyprus, Czech Republic, Denmark, Djibouti, Dominica, Dominican Republic, Ecuador, Egypt, El Salvador, Equatorial Guinea, Eritrea, Estonia, Falkland Islands (Malvinas), Faroe Islands, Fiji, Finland, France, French Guiana, French Polynesia, French Southern Territories, Gabon, Gambia, Georgia, Germany, Gibraltar, Greece, Greenland, Grenada, Guadeloupe, Guatemala, Guernsey, Guinea, Guinea-Bissau, Guyana, Haiti, Heard Island and McDonald Islands, Holy See (Vatican City State), Honduras, Hong Kong, Hungary, Iceland, India, Indonesia, Ireland, Isle of Man, Israel, Italy, Jamaica, Japan, Jersey, Jordan, Kazakhstan, Kenya, Kiribati, Korea, Republic of, Kuwait, Kyrgyzstan, Lao People's Democratic Republic, Latvia, Lebanon, Lesotho, Liberia, Liechtenstein, Lithuania, Luxembourg, Macao, Madagascar, Malawi, Malaysia, Maldives, Mali, Malta, Marshall Islands, Martinique, Mauritania, Mauritius, Mayotte, Mexico, Micronesia, Federated States of, Moldova, Monaco, Mongolia, Montenegro, Montserrat, Morocco, Mozambique, Namibia, Nauru, Nepal, Netherlands, New Caledonia, New Zealand, Nicaragua, Niger, Niue, Norfolk Island, Northern Mariana Islands, Norway, Oman, Palau, Palestinian Territory, Occupied, Papua New Guinea, Paraguay, Peru, Philippines, Pitcairn, Poland, Portugal, Qatar, Republic of North Macedonia, Reunion, Romania, Russian Federation, Rwanda, Saint Barthélemy, Saint Helena, Ascension And Tristan Da Cunha, Saint Kitts and Nevis, Saint Lucia, Saint Martin (French Part), Saint Pierre and Miquelon, Saint Vincent and the Grenadines, San Marino, Sao Tome and Principe, Senegal, Serbia, Seychelles, Sierra Leone, Singapore, Sint Maarten, Slovakia, Slovenia, Solomon Islands, Somalia, South Africa, South Georgia and the South Sandwich Islands, South Sudan, Spain, Sudan, Suriname, Svalbard and Jan Mayen, Swaziland, Sweden, Switzerland, Taiwan, Province of China, Tajikistan, Tanzania, United Republic Of, Thailand, Timor-Leste, Togo, Tokelau, Tonga, Turkey, Turkmenistan, Turks and Caicos Islands, Tuvalu, Uganda, Ukraine, United Arab Emirates, United Kingdom, United States, United States Minor Outlying Islands, Uruguay, Uzbekistan, Vanuatu, Venezuela, Vietnam, Virgin Islands, British, Wallis and Futuna, Western Sahara, Zambia, Zimbabwe
Humanity is under siege as the full force of Mental’s hordes spread across the world, ravaging what remains of a broken and beaten civilization. The last remaining resistance to the invasion is the Earth Defense Force led by Sam “Serious” Stone and his heavily-armed squad of misfit commandos.
Croteam returns with a high-powered prequel to the Serious Sam series that scales up chaos to unprecedented levels. The classic Serious Sam formula is revamped by putting an unstoppable arsenal up against an unimaginable number of enemies that requires players to circle-strafe and backpedal-blast their way out of impossible situations.
HORDES OF INVADERS
The iconic cast of alien invaders returns with some new reinforcements! Fight your way through unbelievable numbers of Mental's minions including the iconic Headless Kamikaze, Beheaded Rocketeer, Kleer, Scrapjack, Werebull, and Khnum! Square off against brand new enemies and towering monsters like the frantic Processed, repulsive Belcher, the hard-hitting Zealot, and more.
EXPLOSIVE ARSENAL
Armed with a slew of devastating weapons, pick your tool for any situation. Lay waste to Mental's Horde using the powerful double-barreled shotgun, the punishing minigun, the powerful chainsaw launcher, a brand new auto shotgun, and the iconic cannon. Upgrade your toys, and enjoy the violent beauty of the lock-on rocket launcher, and the mighty laser beam of death.
COOPERATIVE MAYHEM
Smash through the action-packed campaign with friends in 4-player online co-op mode! Tackle exciting primary missions and thrilling side quests in modified difficulties for an extra challenge.
LEGION SYSTEM
Serious Sam 4 unleashes some of the biggest moments in the series’ history with the new Legion System and battlefields teeming with thousands of enemies!
Login or register at the official Steam Website and download Steam client
Install and start application, login with your Account name and Password
Click the Games Menu.
Choose Activate a Product on Steam...
Follow the onscreen instructions to complete the process
After the successful code verification, go to the "MY GAMES" tab and start downloading.
News & Updates
2025-04-30
Monthly Recap - April Edition
For this month’s recap of interesting events in gaming we have prepared a few different stories that stood out to us in their own ways. One is about a classic FPS getting an interesting experimental generative AI version that could disrupt the industry forever, the next one is about a remastered fan-favorite as well as its incredible reaches to new heights and the third is about a current hit title that is strikingly breaking grounds on the scene in just mere days from its official release…
One of our favorite sci-fi days is here and we are happy to announce yet another promotion for May the 4th be with you a.k.a. Star Wars Day, it has become a tradition for fans across the world to have a dedicated time of the year for the popular movie and game franchise by Lucasfilm Games. YUPLAY will join the celebration by randomly picking 20 lucky customers that will get full refunds on their orders in YU Coins during the promotional period…