Steam Playtests
Hostile Mars

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Hostile Mars playtest

by Big Rook Games

Hostile Mars is a factory-building game focused on combat! Explore an open world and discover new tech to unlock powerful weapons and structures. Create efficient supply chains using delivery bots. Salvage destroyed enemies for resources. Design your base to withstand increasing waves of enemies!

Join playtest Steam store page

Anyone with a Steam account can join, and it's free.

Access
Instant
On playtest since
Nov 1, 2026
Planned release
Coming soon
Developer
Big Rook Games
Platforms
Windows
Players
Co-op, Multiplayer, Online co-op, Single-player
Languages
Arabic, Bulgarian, Czech, Danish and 25 more

How to join the Hostile Mars playtest

  1. Open the game's Steam page with the Join playtest button. Sign in to Steam if it asks.
  2. Use the Hostile Mars playtest signup there. You're in straight away, with nothing to pay.
  3. The playtest shows up in your Steam library, ready to install and play.

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About Hostile Mars

Hostile Mars is a factory-building game with a focus on insane waves of combat against many different types of enemies. Create efficient supply chains, salvage destroyed enemies, and upgrade your structures to support gigantic cannons and a multitude of traps/obstacles to defend your base against thousands of enemies who want to ruin your day.

UPGRADE GIGANTIC GUNS

Upgrade everything to an insane degree and then beyond. Laser turrets come in sizes 1, 2, 3 or ridiculous. Go with ridiculous. Trust us.

BATTLE THOUSANDS OF ENEMIES

Wave after wave of enemy drones pour over the hills and tower above you. Strengthen your base to tower over THEM. You'll need every upgrade you can get your hands on to defend against the robots and those who have sent them against you.

AUTOMATE YOUR SUPPLY CHAIN

Who has the time to manually defend your base and acquire supplies? Create supply lines by automating a small army of delivery bots to harvest ore and resupply your base for you.

FEATURES

  • Customize and upgrade your turrets and traps to deal more damage, shoot farther/faster and hit harder!
  • Collect materials from defeated enemies as you automate your own drones to harvest materials from the Martian landscape for you!
  • Upgrade your base and your character to unlock new items, abilities and weapons!
  • Strategically place walls, traps, and turrets to create a defense strong enough to keep your enemies at bay and your home base energy core protected. Engineer your way to victory!
  • Explore a beautifully-rendered Martian surface to find hidden structures and resources to use against your enemies!

From the game's Steam page.

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