Top similar games like Alien Swarm:

Play Evolve for free with Evolve Stage 2! Evolve Stage 2 is a next-generation free multiplayer shooter featuring addictive 4v1 gameplay. One player-controlled monster must evade and outsmart a team of four uniquely skilled hunters.

Embark on a cosmic journey! Choose your role: Pilot, Engineer, First Mate, or Commando. Conquer the stars with intense teamplay, powerful upgrades, and thrilling battles. Take command, repair systems, or unleash chaos. Victory awaits in this immersive space adventure!

Play with 1-4 players online or local in this co-op roguelike game as you and the crew manage a vehicle to escape this crazy world.

Gather a squad and fight for survival in We're All Going To Die. Work together with a squad using abilities, equipment and exploring different levels to make the most of your fight against your demise, after all, you're all going to die at some point.

Warface: Clutch is a contemporary MMO first person shooter with millions of fans around the world. It offers intense PvP modes, compelling PvE missions and raids that you can challenge with five diverse classes and a colossal customizable arsenal.

Starship Troopers: Extermination is a 16-player co-op FPS that puts you on the far-off frontlines of an all-out battle against the Bugs! Squad up, grab your rifle, and do your part as an elite Deep Space Vanguard Trooper to take back planets from the Arachnid threat!

ROGUE SHIFT is a high-intensity top-down shooter, set on a harsh planet that will test your will to survive. To stay alive, you will pit yourself against hordes of relentless enemies in an unforgiving, hostile environment.

The System built a world of injustice and oppression. Pressed up against the wall, it now fights for its survival. Uphold the law as an elite police officer or join the Stagers to liberate the world, defining the future of society in this multiplayer isometric tactical shooter!

Dive into thrilling team conflicts in an action-packed Hero Shooter incorporating unique MOBA elements. Customize your hero combat style with a singular card system. Control key zones, gather resources, and steal essence from enemy bases to claim victory for your squad. Join The Harvest!

Thunder Tier One is a realistic top-down shooter where you join an elite special operations team tasked with stopping a dangerous terrorist organization wreaking havoc across the fictional Eastern European country of Salobia.

Netherverse is a Free-to-play, Third-person, Team-based, 3v3 Multiplayer Deathmatch online game set in a dystopian world. Team up, choose a class & fight to survive. Discover our unique world shifting mechanic, as well as the Human & the Nether worlds.

- Co-op Twin Stick Shooter

A retro Sci-Fi First Person/Third Person shooter game similar to Star Wars: Battlefront and Rogue Squadron series. The player can choose to battle the alien race and their monster creations in Single-Player or in Multiplayer mode.

2280 A.D. The last few survivors of a ruined Earth seek a new home: Mars, a planet whose inhabitants didn't take too kindly to outsiders. The Red Solstice is a tense, tactical, squad-based action game. Fight to survive with up to 8 players in co-op, or lead your own squad in single-player mode.

17.waves is an online co-op tower defense game for two to four players. Strategize with your teammates to build, upgrade, and maintain your towers to defend your base from hordes of enemy monsters.

The Earth is in pieces...again! We've gotta do more to save the planet!

Brace yourself for explosive space battles in GalaxIverse II! This intense multi-directional shooter puts you in the pilot's seat against alien fleets and colossal capital ships.

It's a fight for the future of the planet between the Ravagers, a merciless swarm of alien invaders, and the Earth Defense Force (EDF) in this third-person shooter.Play as four different classes in over 80 missions with a range of 800 weapons at your disposal.Co-op play supported.

Galactic Wars EX is a pixel perfect co-op retro arcade shmup retrogaming experience for modern pcs

Experience the explosive science fiction arcade-shooter that resurrects a much revered franchise in an epic single player and co-op multiplayer campaign.

Surviving is only half the game. The award-winning atmosphere and gameplay mechanics of the original Shadowgrounds make a triumphant return in this spin off/sequel armed with a slick new feature set! Shadowgrounds Survivor tells the story of the last remaining humans on Jupiter's moon Ganymede, where the alien onslaught is in full force.

Loopbreaker is a class-based, third-person, action roguelike in which you can go it alone or team up with friends to battle back against the alien invasion by collecting powerful items and outpacing the onslaught.

Humanity Has Been All But Destroyed. Find The Last Remaining Few And Protect Them. Discover Unknown Places Along The Way.

A fast paced multiplayer shooter that pits aliens against humans in a strategic and action-packed struggle for survival!

Gatekeeper is a fast-paced rogue-like. Go on a quest to find the stolen Heart of the Universe and shoot your way through the hordes of machine enemies guarding the planetary gates. Play solo or in 4 people co-op and become the next Guardian!

Kallax is a chaotic furniture-building 2 to 6 players co-op game in which only one player can read the instruction manual at a time. Experience what should have been a one person's job and lose friendships forever.