IMHO.

Single-player games like Invader TD

Below are 9 single-player Steam games similar to Invader TD, ranked by player overlap. Every pick carries Steam's Single-player category, so multiplayer-only titles or always-online games don't sneak in. imho.run pulls the category data from Steam directly — Single-player here matches what the store labels.

Want the full alternatives list (paid + free + Steam Deck + cheaper picks)? See the parent games like Invader TD page.

Ranked picks

  1. 1
    Castle Combat — Steam game cover

    Castle Combat

    Single-player alternative to Invader TD — playable solo, no multiplayer required. Shares Strategy and Casual with Invader TD.

    RTS, but the soldiers will act automatically: Each soldier has different characteristics/attribute values/action methods. Choose the appropriate soldiers and buildings according to the battlefield situation, and destroy the opponent's castle only through your strategy rather than operation!

    2025StrategyCasual2.99 USDSingle-playerSimilar games →
  2. 2
    Kings of Cratia — Steam game cover

    Kings of Cratia

    Single-player alternative to Invader TD — playable solo, no multiplayer required. Shares Strategy and Indie with Invader TD.

    Kings of Cratia offers an experience that mixes real-time strategy and first-person shooter mechanics. Build your new village and manage your resources efficiently. Be ready to defend your village every day when night falls! RTS or FPS, you are free to protect your village any way you want it.

    2025ActionStrategyIndie4.99 USDSingle-playerSimilar games →
  3. 3
    Mechanocide: Fortress Omega — Steam game cover

    Mechanocide: Fortress Omega

    Single-player alternative to Invader TD — playable solo, no multiplayer required. Shares Strategy and Indie with Invader TD.

    On a forgotten world, confront a malevolent machine intelligence. Extract minerals, build factories, power up the railguns, and arm the missile batteries. Defend the Fortress Omega against the alloyed nightmare.

    StrategyIndieSingle-playerSimilar games →
  4. 4
    Castle Push — Steam game cover

    Castle Push

    Single-player alternative to Invader TD — playable solo, no multiplayer required. Shares Strategy and Indie with Invader TD.

    Castle Push is a fantasy and strategy game developed by Blue Cat Studio. Play the classic browser strategy. Complete all levels and unlock all possible achievements in this game. And listen to the best music from Haindale.

    2023StrategyIndieCasual0.99 USDSingle-playerSimilar games →
  5. 5
    Dwarven Village — Steam game cover

    Dwarven Village

    Single-player alternative to Invader TD — playable solo, no multiplayer required. Shares Strategy and Casual with Invader TD.

    Dwarven Village is a tower defense game that you place your units to enemy paths and towers to the sides to support, Open chests, Unlock new troops & towers and use synergies between them

    2026StrategyCasualSingle-playerSimilar games →
  6. 6
    Automatrons - Tower Defense — Steam game cover

    Automatrons - Tower Defense

    Single-player alternative to Invader TD — playable solo, no multiplayer required. Shares Strategy and Indie with Invader TD.

    Join our machine legion to conquer the world.

    2023ActionStrategyIndie3.99 USDSingle-playerSimilar games →
  7. 7
    The Unearthened - Complete Edition — Steam game cover

    The Unearthened - Complete Edition

    Single-player alternative to Invader TD — playable solo, no multiplayer required. Shares Strategy with Invader TD.

    Build & defend a small remote mining base on Taichin XI from the alien hordes. Deploy defenses, upgrade your turrets and get ready for the nightfall. The Unearthened is a classic Idle Tower Defense game where you build towers and prepare for the invasion.

    2023StrategySimulation7.99 USDDeck PlayableSingle-playerSimilar games →
  8. 8
    PENGUINS VS SEALS — Steam game cover

    PENGUINS VS SEALS

    Single-player alternative to Invader TD — playable solo, no multiplayer required. Shares Indie with Invader TD.

    PENGUINS VS SEALS is a side-scrolling real-time strategy game that blends tower defense and unit deployment. Build production structures, command your forces, and push the frontline forward using tactical decisions and battlefield abilities.

    IndieSingle-playerSimilar games →
  9. 9
    Cato, the cat — Steam game cover

    Cato, the cat

    Single-player alternative to Invader TD — playable solo, no multiplayer required. Shares Casual with Invader TD.

    Take care of Cato using a match 3 mechanic and don't let him get away.

    2022Casual1.99 USDSingle-playerSimilar games →