Single-player games like Alien Swarm: Reactive Drop
Below are 9 single-player Steam games similar to Alien Swarm: Reactive Drop, 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 Swarm: Reactive Drop page.
Ranked picks
- 1

Alien Swarm
Single-player alternative to Alien Swarm: Reactive Drop — playable solo, no multiplayer required. Shares Action and Free To Play with Alien Swarm: Reactive Drop.
Co-operative multiplayer game and complete code base available for free.
- 2

Portable Ops
Single-player alternative to Alien Swarm: Reactive Drop — playable solo, no multiplayer required. Shares Action with Alien Swarm: Reactive Drop.
In POPS, every bullet fired pushes you further into the chaos of war. The story-driven campaign throws you into the boots of an elite operative. Fight through a series of intense missions, face overwhelming odds, unexpected betrayals, and brutal firefights where only the strongest survive.
- 3

Mauled Horde
Single-player alternative to Alien Swarm: Reactive Drop — playable solo, no multiplayer required. Shares Action and Free To Play with Alien Swarm: Reactive Drop.
Mauled Horde is a Free-To-Play indie Third-Person Shooter made by a solo developer. Play solo or in online co-op squads of up to 3 players. Fight relentless hordes across varied maps, collect weapons, activate traps, buy upgrades, and survive rising difficulty round after round.
- 4

Morte Accendere
Single-player alternative to Alien Swarm: Reactive Drop — playable solo, no multiplayer required. Shares Action with Alien Swarm: Reactive Drop.
A sci-fi zombie infected third or first person action with elements of parkour, combat with weapons or hand to hand, many modes of transportation. Ability to craft items and build your safe zone.
- 5

EARTH DEFENSE FORCE 5
Single-player alternative to Alien Swarm: Reactive Drop — playable solo, no multiplayer required. Shares Action with Alien Swarm: Reactive Drop.
Stand and fight for humanity. This arcade shooter takes place in the year 2022, as the Earth Defense Force fends off an all-out attack by unknown life forms. Become an EDF soldier, battle against endless hordes of immense enemies, and restore peace to the earth.
- 6

Alien Breed: Impact
Single-player alternative to Alien Swarm: Reactive Drop — playable solo, no multiplayer required. Shares Action with Alien Swarm: Reactive Drop.
Experience the explosive science fiction arcade-shooter that resurrects a much revered franchise in an epic single player and co-op multiplayer campaign.
- 7

Perfect Heist 2
Single-player alternative to Alien Swarm: Reactive Drop — playable solo, no multiplayer required. Shares Action with Alien Swarm: Reactive Drop.
Perfect Heist 2 is a round-based online game, where robbers try to hide in plain sight while robbing a bank without being noticed by the cop team!
- 8

Shadowgrounds Survivor
Single-player alternative to Alien Swarm: Reactive Drop — playable solo, no multiplayer required. Shares Action with Alien Swarm: Reactive Drop.
Surviving is only half the game. The award-winning atmosphere and gameplay mechanics of the original Shadowgrounds make a triumphant return in this spin off/sequel armed with a slick new feature set! Shadowgrounds Survivor tells the story of the last remaining humans on Jupiter's moon Ganymede, where the alien onslaught is in full force.
- 9

Portal 2
Single-player alternative to Alien Swarm: Reactive Drop — playable solo, no multiplayer required. Shares Action with Alien Swarm: Reactive Drop.
The "Perpetual Testing Initiative" has been expanded to allow you to design co-op puzzles for you and your friends!