IMHO.

Free games like Iron Sky: Invasion

Below are 8 free-to-play Steam games similar to Iron Sky: Invasion, ranked by player overlap and content similarity. No purchase or Steam login required to view the list. Every pick is a full free-to-play title — not a demo, trial, or time-limited giveaway. imho.run's catalogue refreshes daily, so newly free or newly popular titles surface here without manual editing.

Want the full alternatives list (paid + free + Steam Deck + cheaper picks)? See the parent games like Iron Sky: Invasion page.

Ranked picks

  1. 1
    Ultimate Custom Night — Steam game cover

    Ultimate Custom Night

    Free-to-play alternative to Iron Sky: Invasion — no purchase or trial window. Shares Action with Iron Sky: Invasion.

    Welcome to the ultimate FNAF mashup, featuring 50 selectable characters and custom difficulties!

    2018ActionIndieFree To PlayFreeFree to playSimilar games →
  2. 2
    The Lab — Steam game cover

    The Lab

    Free-to-play alternative to Iron Sky: Invasion — no purchase or trial window.

    Welcome to The Lab, a compilation of Valve’s room-scale VR experiments set in a pocket universe within Aperture Science. Fix a robot, defend a castle, adopt a mechanical dog, and more. Still not sold? It’s free!

    2016Free To PlayFreeFree to playSimilar games →
  3. 3
    Epic Battle Fantasy 3 — Steam game cover

    Epic Battle Fantasy 3

    Free-to-play alternative to Iron Sky: Invasion — no purchase or trial window.

    Epic Battle Fantasy 3 is a silly turn-based JRPG, full of useless NPCs, rabid cats, childish humor, unreasonably large weapons, anime boobs, and other nonsense. And it's totally free!

    2016IndieAdventureRPGFreeDeck PlayableFree to playSimilar games →
  4. 4
    The Riftbreaker: Prologue — Steam game cover

    The Riftbreaker: Prologue

    Free-to-play alternative to Iron Sky: Invasion — no purchase or trial window. Shares Action and Strategy with Iron Sky: Invasion.

    The Riftbreaker: Prologue allows you to experience the events taking place before the story campaign of the main game. Explore an entirely new world. Gather resources. Build up a base. Defend yourself from thousands of alien creatures.

    2020ActionStrategyIndieFreeDeck PlayableFree to playSimilar games →
  5. 5
    PlanetSide 2 — Steam game cover

    PlanetSide 2

    Free-to-play alternative to Iron Sky: Invasion — no purchase or trial window. Shares Action with Iron Sky: Invasion.

    PlanetSide 2 is an all-out planetary war, where thousands of players battle as one across enormous continents. Utilize infantry, ground and air vehicles, and teamwork to destroy your enemies in this revolutionary first-person shooter on a massive scale.

    2012ActionMassively MultiplayerFree To PlayFreeDeck PlayableFree to playSimilar games →
  6. 6
    AdVenture Capitalist — Steam game cover

    AdVenture Capitalist

    Free-to-play alternative to Iron Sky: Invasion — no purchase or trial window.

    Welcome, eager young investor, to AdVenture Capitalist! Arguably the world's greatest Capitalism simulator!

    2015IndieFree To PlayCasualFreeDeck PlayableFree to playSimilar games →
  7. 7
    Fallout Shelter — Steam game cover

    Fallout Shelter

    Free-to-play alternative to Iron Sky: Invasion — no purchase or trial window. Shares Simulation with Iron Sky: Invasion.

    Fallout Shelter puts you in control of a state-of-the-art underground Vault from Vault-Tec. Build the perfect Vault, keep your Dwellers happy, and protect them from the dangers of the Wasteland.

    2017SimulationRPGFree To PlayFreeDeck VerifiedFree to playSimilar games →
  8. 8
    Clicker Heroes — Steam game cover

    Clicker Heroes

    Free-to-play alternative to Iron Sky: Invasion — no purchase or trial window. Shares Strategy and Simulation with Iron Sky: Invasion.

    Click your way through hordes of monsters, earn gold, and recruit quirky heroes with powerful skills. Progress even while you're idle, and watch the numbers climb into the absurd. It’s a never-ending journey of clicks, crits, and colossal damage.

    2015StrategyIndieAdventureFreeFree to playSimilar games →