Single-player games like Alien Defense
Below are 16 single-player Steam games similar to Alien Defense, 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 Alien Defense page.
Ranked picks
- 1
Tower Defense: Last Castle
Single-player alternative to Alien Defense — playable solo, no multiplayer required. Shares Indie with Alien Defense.
In the depths of an ancient forest, your castle the last human stronghold stands as the final bastion against a monstrous horde. Strategize your defense by employing soldiers, traps, towers, and even the monsters themselves.
- 2
Throbax TD
Single-player alternative to Alien Defense — playable solo, no multiplayer required. Shares Action and Indie with Alien Defense.
Throbax TD is the "Tower Defense" game you are looking for: Help Ughlar fight his way through 50 levels, buy over 100 upgrades and get all of the 50+ achievements.
- 3
Empires in Ruins
Single-player alternative to Alien Defense — playable solo, no multiplayer required. Shares Indie and RPG with Alien Defense.
The bastard child of Grand Strategy and Tower Defense, with a black humor infused plot, set in a grim, disillusioned world. Quell the rebellion, tame the Western Marches, disobey your orders and save your brandy. Not strictly in this order.
- 4
Halloween Defense
Single-player alternative to Alien Defense — playable solo, no multiplayer required. Shares Action and Indie with Alien Defense.
The top of strategy battle game! Build villages and train units to defeat ghouls
- 5
Warpips
Single-player alternative to Alien Defense — playable solo, no multiplayer required. Shares Action and Indie with Alien Defense.
Warpips is the ultimate quick to learn but amazingly deep tug-of-war strategy game. Deploy the right composition of soldiers, tanks, helicopters and planes in this tight, streamlined strategy-focused war game. Compose the best army, research the right tech; overwhelm your enemy!
- 6
Dread Dawn
Single-player alternative to Alien Defense — playable solo, no multiplayer required. Shares Action and Indie with Alien Defense.
This is an open-world zombie survival game set in a quarantined city. You play as a student left behind due to missing the evacuation convoy. Together with classmates and other survivors, you must defend the school, survive, and await rescue.
- 7
Alien Hallway
Single-player alternative to Alien Defense — playable solo, no multiplayer required. Shares Action and Indie with Alien Defense.
Players measure stamina with a never-ending stream of green creatures within the borders of a special military mission.
- 8
McDROID
Single-player alternative to Alien Defense — playable solo, no multiplayer required. Shares Action and Indie with Alien Defense.
Farm, Build, Defend, in the Galaxy's only Arcade-Tower-Defense.
- 9
Moonlight Warrior
Single-player alternative to Alien Defense — playable solo, no multiplayer required. Shares Action and Indie with Alien Defense.
One person developer made marvelous turn-based game which can beat 43 stages
- 10
Zombie Rush : Extinction
Single-player alternative to Alien Defense — playable solo, no multiplayer required. Shares Action and Indie with Alien Defense.
The top of strategy battle game! Build villages and train units to defeat zombies
- 11
For Inco
Single-player alternative to Alien Defense — playable solo, no multiplayer required. Shares Action and Indie with Alien Defense.
This is a RPG game that grows through killing monsters to raise levels and create various items.
- 12
Dragon Stone - Legendary Archer
Single-player alternative to Alien Defense — playable solo, no multiplayer required. Shares Action and Indie with Alien Defense.
This game is a hero defense game where you have to collect items and raise your hero's stats quickly in order to stop the monsters which getting stronger gradually.
- 13
Tower of God
Single-player alternative to Alien Defense — playable solo, no multiplayer required. Shares Action and Indie with Alien Defense.
Turn-Based Action RPG
- 14
Zombie Rush - Heroes
Single-player alternative to Alien Defense — playable solo, no multiplayer required. Shares Action and Indie with Alien Defense.
Build villages and train units to defeat zombies
- 15
Kingdom of Heroes
Single-player alternative to Alien Defense — playable solo, no multiplayer required. Shares Action and Indie with Alien Defense.
An RPG game that grows by defeating monsters to level up and making a variety of items.
- 16
a survivor girl
Single-player alternative to Alien Defense — playable solo, no multiplayer required. Shares Action and Indie with Alien Defense.
A girl who crashes on exoplanet begins to survive desperately.