Top similar games like Astra Sentinel:

Diplomacy is Not an Option: Shareware is a free prequel to the original game. In a medieval fantasy world, you are to build settlements, raise huge armies, and defend against massive hordes of enemies. Learn how Ironbrow clan shaped the world's map the first time - if you survive, that is.

A tower defense with a twist - you’re defending a nuclear bomb. It powers your defenses, but the more you use it, the closer you get to meltdown. Manage chaotic engineers, scarce resources and risky upgrades - every decision counts.

Grow out your defenses and defend against waves of invasive enemies. Manage resources, explore further out into the wilds, and strengthen your grove. Wild Growth TD combines tower defense with real time strategy and rogue-lite elements.

Build. Defend. Survive. Expand. A sci-fi base-building game on a hostile alien world. Gather resources, build a sprawling high-tech colony, and defend against relentless alien threats—then unlock new planets, new challenges, and the secrets of humanity’s last frontier.

Frostpunk is the first society survival game. As the ruler of the last city on Earth, it is your duty to manage both its citizens and infrastructure. What decisions will you make to ensure your society's survival? What will you do when pushed to breaking point? Who will you become in the process?

A 2D Strategic Base Defender game set in Medieval times. As relentless Waves of enemy forces threaten your Stronghold, you must gather Resources, Fortify your Defenses and lead your Rebellion. Prepare to strengthen your Base and manage your Resources. But beaware of the Storms!

Tower-defense mixed with economy elements. It features complex skill trees, resource trading, building your own village, and setting individual tactics for each tower. Can you defend what you've built from hordes of enemies? Visit Ancient Islands and test your tactical sense!

Terminal squad: swarmites is a game with indirect control where you must erect a chain of buildings, which generate resources for construction or the combat units for destruction of an enemy.

Atom Assault throws you into a chaotic Red vs Blue war where everything explodes, infantry fish for money, and you can even pilot nukes in first person. Full 3D, fully destructible world, fast, funny, proudly indie. If you miss old school RTS mayhem, this one hits hard.

Prologue version of Orc Warchief. Become an Orc warchief and fight for survival of your race. Rebuild your village and train your warriors. Gather resources and craft your weapons. Raise your warbanner and gather The Horde.

Cosmic Stronghold is a mix of the genres RTS and Tower Defense. Your primary goal is to keep your space station alive for as long as possible, so that it can harvest the nearby mines for precious mineral ores. You will be faced with waves of enemies, getting stronger and stronger for each wave.

Eons of War is a survival RTS with indirect control. Build a colony for autonomous spaceships, terraform and protect planets from star radiation, and survive against the waves of enemies from the mysterious Rift.

A full reimagining of Frostpunk, the groundbreaking survival city builder, packed with new content. In a world ravaged by endless frost, become the Captain of the last city on Earth. Manage its people and infrastructure while facing cruel weather and even crueler choices.

In this Procedural City-Building and Survival game, you must manage your resources, expand your village, assemble an army and destroy the source of evil, which changed the entire eco system of a land that was once prosperous and peaceful.

Manage a space station, flying through a procedually generated universe, fight, build and survive in the coldness of space.

IXION is an unrelenting, city-building odyssey across the stars. As Administrator of the Tiqqun, DOLOS’ prototype space station, you are tasked with balancing preservation and exploration as you manage infrastructure, resources and crew. Can you keep the flame of humanity alight in the cold dark?

Choose between 4 factions and wage war against your enemies in this real-time strategy game. Insect Empires is a cartoon style Isometric real-time strategy game about colony type insects. Choose your faction and wage war against any foe!

Build towers, manage resources, and lead units to defend your kingdom against goblins. Every decision you make determines your kingdom's fate.

Frontier Control: Invasion is a Real-Time Strategy survival game in which you play the commander of a human space colony under the attack of outer space robots. Build your base, train your colony, and fight herds of enemies and bosses.

A strategy game with a new kind of enemy, Calyx puts you in charge of a space mining outpost, locked in battle against powerful plant-aliens. Build your base, gather resources, assemble your forces, and take on the Calyx. With only an out-of-date AI for company, can you survive?

Survival is temporary. Legacy is forever. Rule the last colony on Mars in this RTS x Colony Sim. Build domes for colonists as they harvest crops to survive, and command Mech armies against endless Marsect swarms. With hostile enemies and climate threatening your expedition, every choice matters.

In Anno 2205™, you join humankind‘s next step into the future with the promise to build a better tomorrow. You conquer Earth, establishing rich, bustling cities and grand industrial complexes, but to secure the prosperity of your people, you must travel into space.

Here Comes the Swarm is a survival RTS with a pause button! Create your strategy, build, manage, and defend your settlements at your own pace. Take the fight to the hive mind and lead expeditions to deliver a deadly blow and eradicate your foes. Will you reclaim Ulora from the relentless Swarm?

Guide a group of space settlers trying to establish a base on a remote planet. Grow food, collect energy, mine resources, survive disasters and build a self-sufficient colony in a harsh and unforgiving environment.

In Space Drilling Station, manage a drilling station on a distant planet. Build a multi-level vertical structure to produce and manage your resources and staff, in order to dominate the competition!

On planets occupied by robots, mine resources and escape while fending off their attacks! The Ark's survival is entirely in your hands. Many elite crews with abilities will assist you in your mission. The various turret modules are always doing their best to defend your base without your attention.

A strategic and action-packed base survival game where you mine crystals, build units, and defend your base against waves of UFOs. Defeat enemies, gather resources, and unlock new planets to expand your defenses. Are you ready to conquer the galaxy?

Take command of the fleet of starships that is the home to the remnants of your civilization. Manage the limited space of each spacecraft and find the balance between living space, production, defenses, and weapons. Explore the galaxy as you seek refuge and safety from an overwhelming threat.

Get ready to protect the entire solar system from an unprecedented threat - the D'Ahari, a race of insect-like aliens. Control an entire fleet of spaceships, trade with other races of an Alliance, and develop your own space station.

Strategy by day, tactical tower defense by night. Build a bunny colony, manage resources, and defend against nightly monster attacks in this mix of city building and tower defense. Help your bunnies escape to the stars before the darkness destroys everything.

Warfactory is an automation RTS where production defines the war effort. Build assembly lines to forge an army of machines, then feed thousands of units into massive real-time battles where every loss must be replaced by your factory.