Top similar games like Classic Marathon:

In the future, humans conquered the stars and colonized other planets. In the bowels of the icy planet, scientists have discovered a natural and safe source of energy. But at the same time, they awakened an ancient alien life form. There is a conflict on the planet. Volunteers come to the rescue.

Action heavy, multiplayer + singleplayer FPS set in a brutal cyberpunk universe.

From one of gaming's most iconic sagas, Halo is bigger than ever. Featuring an expansive open-world campaign and a dynamic free to play multiplayer experience. 

EXIMIUS is a FPS/RTS hybrid that focuses on squad-based combat. The game features an intense 5v5 multiplayer experience with each team comprising of 4 Squad Officers and one Commander.

Experience the next generation of VR combat with Evasion, an intense sci-fi bullet-hell shooter. Play solo or team up with a friend as you run, dodge, and unleash devastating Surge Attacks as you fight your way through an action-packed story campaign.

MECHWARRIOR 5: CLANS follows a Star of Clan Smoke Jaguar warriors during Operation REVIVAL, a full-scale invasion of the Inner Sphere. Armed with an arsenal of cutting-edge BattleMechs, meticulously designed maps and missions deliver immersive and intricate tactical gameplay and combat experiences.

Fight for survival! Industrial waste has disturbed the dangerous Kaeru-tori's habitat, forcing them into the city. Unlock new areas, purchase weapons and upgrades to grow stronger, and fight off the horde with your friends!

Astral Horizon is a first-person space opera adventure featuring combat with six degrees of freedom. Give orders to your squadmates and find creative ways to approach combat in zero-gravity. Explore epic sci-fi locations as you fight a war to uncover a perspective-shattering discovery.

Relentless Frontier is a fast paced sci-fi FPS running on the GZDoom Engine, with a strong focus on mobility, strategy, and exploration. Use your Omnistruct to replicate new weapons and abilities to help you traverse the terrain and demolish threats, while escaping from Ross 128-b in one piece.

Universe 51: Tannhäuser Wars is a free-to-play fast-paced multiplayer FPS, taking inspiration from games like DOOM and Quake. In Tannhäuser Wars, two unfamiliar groups are mysteriously teleported to the same location. Since communication between them is impossible or undesirable, they clash!

Try this fast-paced sci-fi shooter as an elite OVERGUN mercenary. Go to the moon base of the EARTH ROBOTICS corporation to destroy an army of various robots under the command of an evil AI.

Space bounty hunter Falco must explore the solar system in search of his ex-girlfriend and destroy the Black Star cult. Collect bounties, upgrade your equipment, explore planets, crack wise & fight aliens in this GZDoom-powered Retro-FPS adventure.

Silica is a crossover of FPS and RTS where up to 3 factions battle for control over the planet of Baltarus. Lead from above as commander, or experience the action first-hand, either alone, or with friends. Join one of two human armies, or hunt them down as the territorial aliens.

Why play any other boring Shooter When you can RUSP! RUSP is the new Fast Paced Movement Shooter that you were waiting for.

A fast-paced VR arcade shooter, where you fire guns, shoot energy bows, and toss explosive spears to defend your base from an alien infestation. The bugs shoot back, so don't forget to duck!

First / third person multiplayer shooter with single and multiplayer AI bots and monster, premade and procedural environments.

Space Wackos is a multiplayer and cooperative FPS game heavily based off of the Halo franchise. Featuring over 10 maps and 2 game modes, players have the freedom fight against each other in free-for-all or as a team in Swarm mode.

You crash land on Novark during a rescue mission. With hostile aliens in a war, nowhere is safe and everything is out to kill you. Fight to survive. Discover secrets. Fight epic bosses. Progress through the story. Survive and escape Novark!

Solo or multiplayer, capture control points on an alien planet. Choose the number of enemies you face and enjoy sweet conquest.

Planet Collectors: Episode Earth is an intense fps shooter game with as much as possible realistic feeling to it. Your goal is collecting enough credits to escape from the map. It is a multiplayer game with 6 players maximum and you can work with other players or betray them, that is up to you.

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 set to take back planets claimed by the Arachnid threat!

Tom Clancy's Rainbow Six® Extraction is a tactical, co-op, PvE first-person shooter where you and your squad face an evolving alien threat. Teamwork, tactics, and flawless execution are key to your survival.

Scifyre League is a multiplayer sci-fi sports/shooter mashup for the virtual-reality platform. It combines soccer, football, ranged and melee weapons, jetpacks and more.

Call of Duty®: Advanced Warfare envisions a powerful future, where both technology and tactics have evolved to usher in a new era of combat for the franchise.Power Changes Everything.

RAID other spaceships, EXPAND your fleet and EXPLORE space in this action packed Shooter to ensure Project Mind doesn´t fall into the wrong hands...

Dive into non-stop action in a movement-based arena shooter, blending some of the most familiar gameplay elements of the genre into a completely new experience, build around the idea to have the most fun with your friends you could possibly have with a movement shooter.

Introducing Ultimus: A Vision of First-Person Shooters, circa 1965.

Join Operation Space Force, a free-to-play team-based shooter that takes place in space. Explore weapon customization and different heroes, your base, fight against enemies, and experience different game modes.