Top similar games like Alien Outpost:

Xeno Crisis is an arena shooter in which up to two players take control of battle-hardened marines embarking on a deadly mission to confront an alien menace! Run and gun your way through thousands of adversaries, searching for survivors, and ultimately facing the origin of the outpost's demise.

ZEROCRON is a straightforward, classical arcade Twin-Stick Shoot-Em-Up with a strong Commodore-Amiga-era feel. Blast asteroids and enemies to burning pixeldust!

Collect synergizing items to create an overpowered character to fight hordes of cyclops monsters. Cyclo Chambers is a fast-paced, top-down arena shooter with light rogue-like elements. 150 items to choose from to create frantic combinations. Different runs every time.

Core Breach is a fast-paced, twin-stick arcade shooter in a pixel art style. Play as a Trojan worm virus, outmaneuvering and destroying antivirus enemies. Upgrade your worm with powerful attacks and skills as you fight to breach the CPU core and uncover its secrets

Aliens have invaded Earth! Towns, cities, deserts, they're everywhere! Take on the role of Earth's last super soldier and confront the alien menace in this intense twin stick shooter!

Jetboy is a retro supercharged jetpacking pixel shooter with a pumping metal soundtrack.

Void Prison is a fast paced, endless arcade twin stick shooter that puts you inside of an ever shrinking ring. Survive by fighting emerging enemies around you and don't get consumed by the void. Complete achievements to unlock new skins and powerups and get on top of the leaderboards!

Survive the waves! Buy weapons and ammo! Unlock new stages! Purchase companions! Solve daily quests and get rewards! Casual Pixel Warrior is a wave shooter where your endurance to last an infinite fight depends on your skill, unlocked weapons and purchased ammo.

Blast your way through waves of space debris in order to reach what is waiting for you on the other side. Find your fighting style with multiple unlockable ships in this fast paced space adventure!

A top down, twin stick shooter inspired by classic retro arcade games with loads of enemies, fast paced bullet hell combat, big boss battles and tons of bullets.

Halo: Spartan Assault brings the excitement of Halo combat to Steam for the very first time. Battle your way through 30 action-packed missions against the Covenant as you explore the origin of the Spartan Ops program featured in Halo 4. *DirectX feature level 10 required. *

A top down 2d pixel art sci-fi shooter. Destroy threats, solve small puzzles, kill bosses in each level to advance to the next. Upgrade your drone with the power-ups and weapons you find around the levels to become increasingly lethal.

Defend Spacebase 19 from the asteroids swarming down on the station! Shoot down waves of stones and equip different powerful weapons. How many waves can you last? A simple nostalgic retro arcade turret defense shooter.

Dwarf Star: 16 bit inspired game where mercenary go shoot shoot on evil alien guys who were accidentally fabricated by the government. Top down space shooter with a mission based structure. However, you can do these missions in plenty of different orders with different amounts of upgrades.

Blast your way through an endless horde of enemies in this pixel art top-down shooter. Collect their remains in order upgrade your character for increased combat abilities. Tekla is a top-down shooter with roguelite elements.

In this unique top-down shooter, originally released in 1987, take on the role of the plucky little Biopton Nimrod, sent on a dangerous mission to rescue his friends from the 'Matrix' prison planets of the Cratons. Contains both the Amstrad CPC and ZX Spectrum versions of the game.

An indie story-driven space shooter with intense battles, escalating enemy waves, and massive boss fights. Choose and upgrade ships, unlock powerful weapons, and protect your allies. Upgrade your base and construct a battleship to take on even stronger enemies. All set to a rock & synth soundtrack.

In the vast depths of space, lies a man with a dark past. Setting himself apart from that old life, and seeking justice against wrongdoing instead of being the cause of it, Captain Righteous uses the Freedom Fighter, his trusty space fighter to search for and combat the evil Captain Buster!

KosmoSquad is a twin-stick arena shooter where you survive as long as you can against an ever-increasing hoard of enemies. Fight alone or with up to three friends and collect star multipliers to maximize your high score. Use your score points to purchase upgrades for your ship and try again!

XenoFeud is an insane top-down twin-stick arcade alien shooter, where you must survive hordes of alien intruders while defending a mysterious object in space.

Galactic Explorers is a top-down 2D retro space shooter inspired by early games such as Galaxian, and Asteroids.

Gem Raider 2 is an old-school move-and-shoot game. Your objective in each room is to destroy all of the Power Gems and return to the teleport pad to exit. Other Gems can also be destroyed to increase your score. There are 20 rooms and each of the 9 types of enemy Gems has unique weapons or skills.

High-speed shmup where survival meets rhythm. Evade waves of enemies to pounding drum and bass soundtrack. Compete globally or battle friends in co-op/PvP. Customize your ship, perfect your run, and claim your spot on the leaderboards.

The Bullet Heaven arcade classic that started it all! Create unique builds, kill ever-growing hordes of contestants and beat your friends' high scores in the retro-futuristic gladiator arena BLOODDOME

Classic multi-directional (360°) shoot 'em up. Navigate your UFO through hazardous environments with dangerous enemies and beat huge bosses!

'Monster Freaks!' is a 2D top-down shooter about making monsters bleed! Featuring classic arcade action with a bunch o' guns, controller support, couch co-op, and punishing boss fights!

Top-down shooter action for the Atari Lynx handheld console. WANTED: Hot gun for hire. Travel to several exotic and dangerous places. Discover several exotic and dangerous aliens and kill them. Kill lots. For cash. Buy more weapons and kill again.

Drawn into your PC by an antivirus, control a multi barrel tank in this Action Roguelike, 2D Shooter. Defeat motherboard viruses to unlock new zones. The 'UPGRADE MACHINE' grants enhancements every 1-10 seconds. Use points to add upgrades in this Arcade, Top-Down Adventure.

Split Drive is a roguelite arena shooter where you have to find your way home through a hostile galaxy, numerous locations and a variety of bosses, all generated procedurally.

Vault Apocalypse is a top-down, roguelite twin-stick arena shooter where you fight hordes of monsters while assembling powerful, synergistic builds. Pick your weapons, refine your build and destroy the keepers of the vault.

Space Redemption is a 2D shooter in which the protagonist is assigned the role of the savior of mankind!

A bombastic bug busting adventure! Play as one of four playable characters in their quest to to free their fellow elves from the clutches of an evil army of spiders. If they crawl, blast em all! Let nothing stand in your way.

A sci-fi action arcade run-and-gun game.

Laboratory X-29 is a sci-fi roguelite-like top-down shooter, where the protagonist takes his chances to escape from the Lab after an accident. Shoot your way out to freedom, clear rooms full of other dangerous experiments, find out the secrets hidden in this place and eat chicken to survive.

80's vector style Twin stick action with a booming soundtrack and permadeath.