- #1 Anomaly: Warzone Earth
97% matchVery Positive87% of 4,668 reviews2011
Dev: 11 bit studios
Windows · Mac · Linux
Median: 2.4 hrsMean: 11.0 hrs≥1hr: 88%
Lead an armored squad through the perils of this reversed tower defense action-strategy game!
Why similar: Strategy 46.2%, Tower Defense 31.4%, Action 9.6%, Sci-fi 8.2%, Indie 3%
Why You'll Like It: The original title that defined the reverse tower defense genre with its unique squad-based tactical gameplay.
- #2 Anomaly 2
96% matchMostly Positive79% of 1,055 reviews2013
Dev: 11 bit studios
Windows · Mac · Linux
Median: 2.5 hrsMean: 4.7 hrs≥1hr: 77%
Anomaly 2 is a sequel to the critically acclaimed Anomaly Warzone Earth. Maintaining the core elements of the original, Anomaly 2 adds plenty of new features: unit morphing, over million tactical combinations, post-apo world and tower defense vs tower offense multiplayer mode.
Why similar: Strategy 43.8%, Tower Defense 32.9%, Action 13%, Sci-fi 6.5%, Indie 3.5%
Why You'll Like It: Expands on the original formula with more complex unit transformations and intense tactical combat.
- #3 Anomaly Defenders
96% matchMostly Positive77% of 676 reviews2014
Dev: 11 bit studios
Windows · Mac · Linux
Median: 3.2 hrsMean: 5.7 hrs≥1hr: 89%
Anomaly Defenders is the closing installment of the Anomaly series. The original incarnation of the Tower Offense sub-genre had players controlling humans fighting alien invaders. Now, the tables have turned. The human counterattack is underway and the alien homeworld is under threat.
Why similar: Tower Defense 44.3%, Strategy 36.9%, Action 12.4%, Sci-fi 3.3%, Indie 3%
Why You'll Like It: A direct spin-off that flips the script, allowing you to play as the alien forces defending against human invaders.
- #4 Anomaly Warzone Earth Mobile Campaign
95% matchMostly Positive79% of 549 reviews2013
Dev: 11 bit studios
Windows · Mac · Linux
Median: 3.1 hrsMean: 6.6 hrs≥1hr: 91%
Anomaly Warzone Earth Mobile Campaign continues Steam's Anomaly Warzone Earth in an extra 15-level campaign. Originally released on mobile devices, the campaign is brought to Steam for PC, Mac and Linux exclusively in Anomaly Bundle. AWE Mobile Campaign turns tower defense on its head.
Why similar: Strategy 49.2%, Tower Defense 24.4%, Action 18.5%, Sci-fi 6.6%, Indie 1.1%
Why You'll Like It: Provides additional tactical missions that maintain the core squad-management mechanics of the main series.
- #5 X-Morph: Defense
94% matchVery Positive92% of 4,073 reviews2017
Dev: EXOR Studios
Windows
Median: 3.0 hrsMean: 5.5 hrs≥1hr: 85%
Unique fusion of a top-down shooter and tower defense strategy. You are the invader! Use destructive weapons or lead your enemies into a maze of towers. Strategize in the build mode by carefully selecting various types of alien towers or throw yourself right into the heat of the battle.
Why similar: Tower Defense 45.6%, Strategy 27.6%, Action 10.4%, Sci-fi 10%, Top-Down 3.1%
Why You'll Like It: A perfect hybrid of top-down shooter and tower defense that forces you to actively participate in the battlefield.
- #6 Defense Grid: The Awakening
94% matchOverwhelmingly Positive96% of 5,303 reviews2008
Dev: Hidden Path Entertainment
Windows
Median: 4.6 hrsMean: 15.1 hrs≥1hr: 91%
Defense Grid: The Awakening is a unique spin on tower defense gameplay that will appeal to players of all skill levels. A horde of enemies is invading, and it's up to the player to stop them by strategically building fortification towers around their base.
Why similar: Tower Defense 64.1%, Strategy 25.5%, Sci-fi 8%, Indie 1.8%, Singleplayer 0.5%
Why You'll Like It: The gold standard for sci-fi tower defense, offering deep strategic planning and satisfying base-building.
- #7 Infested Planet
93% matchVery Positive94% of 3,014 reviews2014
Dev: Rocket Bear Games
Windows
Median: 3.1 hrsMean: 5.9 hrs≥1hr: 88%
Command a team of 5 elite soldiers against an alien horde of 100,000. Surrounded on all sides, you must outmaneuver and outsmart the enemy.
Why similar: Strategy 39.7%, Tower Defense 34.7%, Action 10.8%, Sci-fi 7.8%, Top-Down 3.8%
Why You'll Like It: Focuses on squad-based tactical combat against overwhelming alien swarms, mirroring the intensity of Anomaly.
- #8 Taur
92% matchMostly Positive80% of 2,078 reviews2020
Dev: Echo Entertainment
Windows
Median: 4.2 hrsMean: 6.8 hrs≥1hr: 76%
Taur is an action-strategy sci-fi game. Control the Prime Cannon and unlock all of its powerful weapons and abilities. Build turrets, droids, aircraft and more as you fight to protect the homeworld of the Tauron droids against a relentless invasion. Will your Taur stand against the Imperion warmachine?
Why similar: Tower Defense 46.1%, Strategy 32.1%, Action 9.3%, Sci-fi 8.2%, Indie 2.3%
Why You'll Like It: Combines action-heavy defense with sci-fi aesthetics and persistent base-building mechanics.
- #9 Sentinel 3: Homeworld
91% matchMostly Positive80% of 148 reviews2014
Dev: Origin8Pub: Strategy First
Windows
Median: 3.9 hrsMean: 16.9 hrs≥1hr: 73%
The biggest installment of the award winning Sentinel sci-fi tower defense series now on PC!Take the fight to the alien homeworld and unleash a massive arsenal of weaponry. Get up close and personal on the battlefield in your power armor to execute devastating attacks and support your defenses! * An epic campaign across 20 levels.
Why similar: Tower Defense 62.9%, Strategy 29.9%, Sci-fi 4.6%, Indie 2.6%
Why You'll Like It: A classic sci-fi tower defense game that emphasizes unit upgrades and tactical map control.
- #10 Alien Robot Monsters
91% matchVery Positive85% of 124 reviews2015
Dev: Kraftix Games
Windows · Mac · Linux
Median: 7.0 hrsMean: 11.9 hrs≥1hr: 95%
Epic sci-fi tower defense action with 16-bit era look and feel, pitching your colonists against an almost endless horde of hostile alien robots who strongly oppose your attempts of colonizing their planet! Deluxe version includes the soundtrack!
Why similar: Strategy 43.2%, Tower Defense 33.9%, Action 18.2%, Indie 4.6%
Why You'll Like It: A sci-fi themed tower defense game that captures a retro feel while providing solid tactical challenges.
- #11 Fortified
90% matchMostly Positive74% of 1,720 reviews2016
Dev: Siege Camp
Windows
Median: 3.2 hrsMean: 4.9 hrs≥1hr: 89%
Fortified is an explosive strategy shooter where players will defend the Earth against a menacing Martian invasion in the 1950s. Play as one-of-four pulp inspired heroes as they fight swarms of terrifying robots with an arsenal of Cold War era weapons and experimental technology.
Why similar: Action 75.4%, Tower Defense 14%, Strategy 7.9%, Sci-fi 1.7%, Indie 1.1%
Why You'll Like It: An action-heavy defense game with a 1950s sci-fi aesthetic that requires both shooting and strategic trap placement.
- #12 Sanctum 2
89% matchVery Positive90% of 14,356 reviews2013
Dev: Coffee Stain StudiosPub: Coffee Stain Publishing
Windows · Mac · Linux
Median: 2.8 hrsMean: 6.7 hrs≥1hr: 85%
Sanctum 2 is the sequel to the world’s first Tower Defense/FPS hybrid game. Pick from four unique character classes and embark on a mission to protect the oxygen-producing Cores from hordes of deadly aliens who are threatened by their existence.
Why similar: Tower Defense 59.7%, Strategy 22.9%, Action 8.4%, Sci-fi 7.1%, Indie 1.7%
Why You'll Like It: A unique first-person shooter that requires you to build intricate tower defenses to survive waves of enemies.
- #13 Orcs Must Die! 2
89% matchVery Positive92% of 19,505 reviews2012
Dev: Robot Entertainment
Windows
Median: 5.5 hrsMean: 11.9 hrs≥1hr: 91%
You’ve tossed, burned and sliced them by the thousands – now orcs must die more than ever before! Grab a friend and slay orcs in untold numbers in this sequel to the 2011 AIAS Strategy Game of the Year from Robot Entertainment.
Why similar: Tower Defense 61%, Strategy 24.8%, Action 12%, Indie 1.7%, Singleplayer 0.5%
Why You'll Like It: Blends action-oriented combat with trap-based defense in a way that rewards tactical positioning.
- #14 2112TD: Tower Defense Survival
88% matchVery Positive88% of 428 reviews2023
Dev: Refinery Games
Windows
Get ready for the ULTIMATE tower defense onslaught. Build, deploy, research and upgrade your defenses in this epic, old school RTS inspired sci-fi adventure.
Why similar: Tower Defense 40.7%, Strategy 29.5%, Sci-fi 13.4%, Action 11.2%, Top-Down 4.2%
Why You'll Like It: A top-down sci-fi defense game that emphasizes tactical unit control and survival against massive waves.
- #15 Artificial Defense
87% matchVery Positive82% of 210 reviews2016
Dev: Thiemo Bolder, ONEMANGAMES
Windows
Median: 3.5 hrsMean: 4.9 hrs≥1hr: 95%
Artificial Defense is a one man made, real time strategy game combining orbital shooter and tower defense components within an electrifying, virtual reality setting. You are the machine, a mighty computer-system defending its servers against swarms of intruding creeps.
Why similar: Strategy 50.5%, Tower Defense 24.2%, Action 19.5%, Indie 5.8%
Why You'll Like It: A minimalist strategy game that focuses on efficient tower placement and wave management.
- #16 Creeper World 3: Arc Eternal
86% matchOverwhelmingly Positive96% of 4,761 reviews2014
Dev: Knuckle Cracker
Windows · Mac · Linux
Median: 7.4 hrsMean: 77.0 hrs≥1hr: 78%
Creeper World 3 is what happens when cellular automata takes over a strategy simulation. Instead of discrete units that attack your base, a fluid-like substance spreads over the terraformable terrain. Your base, your weapons, your strategy... you must adapt them all.
Why similar: Tower Defense 62.2%, Strategy 28.4%, Sci-fi 6.2%, Indie 1.8%, Top-Down 1%
Why You'll Like It: Offers a unique strategic experience where you must manage resources and build defenses against a fluid, encroaching enemy.
- #17 GemCraft - Frostborn Wrath
85% matchVery Positive89% of 2,818 reviews2020
Dev: Game in a Bottle
Windows
Median: 3.9 hrsMean: 38.1 hrs≥1hr: 90%
The epic tower defense dark fantasy journey continues! Create powerful gems with various abilities and take on the battle against an endlessly flowing army of monsters, and face the growing darkness as you fight your way back towards the Spiritforge.
Why similar: Tower Defense 46.8%, Strategy 32.6%, Action 13%, Top-Down 5.2%, Indie 1.8%
Why You'll Like It: Features deep, complex tower defense mechanics that reward long-term strategic planning.
- #18 Rush for Glory
86% matchMixed61% of 148 reviews2014
Dev: Parseh Game StudioPub: KATNAPPE SP. Z O. O.
Windows
Median: 24 minMean: 29.8 hrs≥1hr: 34%
Rush for Glory is featuring challenging and rewarding Tower Defense battles, in which players are defending their base against an alien invasion. By strategically building towers and upgrading them, the player can keep his base safely and further progress through the extensive singleplayer campaign.
Why similar: Tower Defense 48.3%, Strategy 38.8%, Action 12.9%
Why You'll Like It: A classic sci-fi tower defense game with diverse upgrade paths and challenging enemy waves.
- #19 Super Sanctum TD
84% matchVery Positive87% of 1,575 reviews2013
Dev: Coffee Stain StudiosPub: Coffee Stain Publishing
Windows · Mac
Median: 1.9 hrsMean: 33.2 hrs≥1hr: 75%
Super Sanctum TD is a retro-styled Tower Defense game that focuses on strategy, customization and replayability. Build advanced mazes and construct powerful towers to prevent alien hordes from reaching the Core!
Why similar: Tower Defense 52%, Strategy 25.1%, Sci-fi 9.9%, Action 8.6%, Indie 2.2%
Why You'll Like It: An isometric tower defense game that provides a retro aesthetic while maintaining solid strategic depth.
- #20 Kingdom Rush - Tower Defense
82% matchOverwhelmingly Positive97% of 16,302 reviews2014
Dev: Ironhide Game Studio
Windows · Mac · Linux
Median: 4.9 hrsMean: 16.3 hrs≥1hr: 86%
Get ready for an epic journey to defend your kingdom against hordes of orcs, trolls, evil wizards and other nasty fiends using a vast arsenal of towers and spells at your command!Fight on forests, mountains and wastelands, customizing your defensive strategy with different tower upgrades and specializations!
Why similar: Tower Defense 61%, Strategy 29%, Action 7.5%, Indie 1.8%, Singleplayer 0.7%
Why You'll Like It: The definitive polished tower defense experience that offers varied unit types and strategic depth.
- #21 Revenge of the Titans
83% matchVery Positive82% of 1,250 reviews2011
Dev: Puppygames
Windows · Mac · Linux
Median: 2.1 hrsMean: 4.4 hrs≥1hr: 82%
The ultimate mash-up of Real-time Strategy and Tower Defense!
Why similar: Tower Defense 52.2%, Strategy 29%, Sci-fi 7.4%, Action 6.9%, Indie 2.8%
Why You'll Like It: A sci-fi tower defense game that incorporates base-building and resource management into its core loop.
- #22 M.A.C.E. Tower Defense
82% matchMostly Positive70% of 61 reviews2017
Dev: EntwicklerX
Windows
M.A.C.E. Tower Defense is a classic tower defense game with unique towers and enemies and an ingame shop system for getting better towers, upgrade existing towers and buy special items.
Why similar: Strategy 41.1%, Tower Defense 31.3%, Action 16.8%, Sci-fi 6.5%, Indie 4.3%
Why You'll Like It: A top-down sci-fi tower defense game that focuses on strategic placement across varied terrain.
- #23 Age of Steel: Recharge
81% matchMixed76% of 334 reviews2016
Dev: Quaint Emerald
Windows · Mac
Median: 4.0 hrsMean: 4.4 hrs≥1hr: 96%
"Age of Steel: Recharge" is a 2D strategy with a view from the side. You're taking the role of commander, who was entrusted the management of the military base. Your mission is to defend a base from the waves of enemies at any price.
Why similar: Strategy 55.2%, Tower Defense 22.9%, Action 17.5%, Indie 4.5%
Why You'll Like It: An action-oriented strategy game that emphasizes fast-paced tower defense and unit deployment.
- #24 PixelJunk™ Monsters Ultimate
80% matchVery Positive81% of 1,280 reviews2013
Dev: Double Eleven
Windows · Mac · Linux
Median: 3.5 hrsMean: 6.7 hrs≥1hr: 93%
Tikiman the Forest Defender is in trouble. Hordes of monsters are sweeping through his realm, hoping to chow down on his offspring – and it’s up to you to defend them. By placing weapon towers at strategic points around the landscape, you can destroy the invaders and save the little ones.
Why similar: Tower Defense 64.4%, Strategy 34.7%, Indie 0.7%, Singleplayer 0.3%
Why You'll Like It: Features a unique take on tower defense where you actively move a character across the map to build and support defenses.
- #25 Sentinel 4: Dark Star
81% matchMostly Positive79% of 63 reviews2015
Dev: Origin8 Technologies Ltd
Windows
Median: 4.1 hrsMean: 4.6 hrs≥1hr: 96%
Want a tactical and strategic tower defense challenge that's packed with options and upgrades? Take command of the dropship Sentinel and do battle across a vibrant sci-fi world.
Why similar: Strategy 50.1%, Tower Defense 30.2%, Sci-fi 14%, Indie 5.6%
Why You'll Like It: The sequel to the classic series, offering refined sci-fi tower defense mechanics and new tactical options.
- #26 Strain Tactics
79% matchVery Positive85% of 239 reviews2017
Dev: Touch Dimensions Interactive
Windows
Median: 3.0 hrsMean: 10.3 hrs≥1hr: 63%
Strain Tactics is a real-time-with-pause tactical game, where you command a squad of soldiers to liberate earth from an alien infestation. Using your helibase, deploy your custom squad and provide air support. Remember to keep your crew sane and motivated while staying clear of alien contamination!
Why similar: Strategy 54.8%, Action 22.3%, Sci-fi 12%, Top-Down 5.5%, Indie 4.9%
Why You'll Like It: A top-down tactical squad management game that shares the intense, sci-fi combat atmosphere of Anomaly.
- #27 Repel The Rifts
74% matchVery Positive86% of 313 reviews2025
Dev: RefinedBearGamesPub: Goblinz Publishing
Windows · Linux
Repel the Rifts is a roguelite tower defense game where you lead a commander through an alien world, uncovering new terrain each wave, drafting powerful upgrades, and constructing defenses to hold back the chaos.
Why similar: Tower Defense 53.9%, Strategy 27.3%, Sci-fi 16.7%, Indie 1.6%, Singleplayer 0.5%
- #28 Steel Storm: Burning Retribution
79% matchMixed60% of 369 reviews2011
Dev: Kot in Action Creative Artel
Windows · Linux
Median: 4.2 hrsMean: 4.2 hrs≥1hr: 81%
Control an advanced hovertank, packed with the most advanced and sophisticated weapons as you fight against extraterrestrial invaders.
Why similar: Action 56.7%, Sci-fi 24.3%, Indie 17.6%, Singleplayer 1.4%
Why You'll Like It: A top-down action shooter that captures the sci-fi combat intensity of the Anomaly series.
- #29 Molten Armor
78% matchMixed62% of 60 reviews2017
Dev: Brutal Muse
Windows
Molten Armor is an action tower defense game with a non-linear story in sci-fi setting! Command defenses and stop hordes of enemies! Fight on land, sea and in the skies!Decisions taken in the heat of battle will change the course of the war.
Why similar: Tower Defense 39.9%, Strategy 31.5%, Action 11.5%, Sci-fi 11.1%, Top-Down 3.3%
Why You'll Like It: A strategy-focused tower defense game that emphasizes managing resources and defending against waves.
- #30 Spoids
77% matchMostly Positive72% of 115 reviews2017
Dev: AirWave GamesPub: BindleBot
Windows
Median: 3.2 hrsMean: 3.6 hrs≥1hr: 77%
Spoids is a challenging throwback to the original brand of tower defense games. Command the Remote Defense Space Station and respond to distress calls of those who are being attacked by the invaders. Travel from planet to planet using your powerful arsenal to hold back the Spoids.
Why similar: Strategy 43%, Tower Defense 32.5%, Action 13.8%, Sci-fi 5.8%, Indie 4.8%
- #31 Island Defense
78% matchMixed53% of 121 reviews2015
Dev: Stereo7 Games
Windows
Median: 4.2 hrsMean: 4.9 hrs≥1hr: 99%
Get ready for modern battles! Defend your islands against evil invaders in jungles! Your team will consist of modern snipers, gunners, rockets, ice towers and other great things. A deep conflict has been brewing between you and the evil invaders. Fight to protect your freedom and liberty.
Why similar: Strategy 44.5%, Tower Defense 39.9%, Action 12.2%, Indie 3.4%
Why You'll Like It: A casual but strategic tower defense game that focuses on positioning and wave control.
- #32 Xeno Command
75% matchVery Positive84% of 55 reviews2022
Dev: ChillyRoomPub: ChillyRoom
Windows
Defend galaxy against Alien invasion in the RTS offline game with roguelike fun
Why similar: Tower Defense 47.6%, Strategy 35.1%, Sci-fi 11.6%, Top-Down 5%, Singleplayer 0.7%
- #33 Harvest: Massive Encounter
77% matchMostly Positive79% of 159 reviews2009
Dev: Oxeye Game Studio
Windows · Mac · Linux
Median: 1.2 hrsMean: 3.9 hrs≥1hr: 54%
Harvest: Massive Encounter is an award-winning real-time strategy game with battles of epic proportions and a unique style of resource management and exploration. Build power plants, mineral harvesters and defense towers and make sure they have sufficient energy to fend off endless hordes of evil aliens.
Why similar: Tower Defense 47.4%, Strategy 41.2%, Sci-fi 6.7%, Indie 4.3%, Singleplayer 0.4%
- #34 Xenonauts
74% matchVery Positive87% of 5,012 reviews2014
Dev: Goldhawk Interactive
Windows · Mac · Linux
Median: 8.2 hrsMean: 19.7 hrs≥1hr: 88%
Xenonauts is a strategy game in which you control a multi-national military organisation defending a Cold War-era Earth from alien invasion, using small squads of persistent soldiers to eliminate the extraterrestrials and recover their technology in turn-based ground combat.
Why similar: Strategy 66.1%, Sci-fi 25.8%, Indie 5.9%, Singleplayer 2.2%
- #35 Towerful Defense: Prologue
72% matchVery Positive88% of 75 reviews2024
Dev: Mini Fun Games
Windows · Mac · Linux
A tower defense action roguelike where you control a single tower to fight against hordes of aliens coming from all directions. Pick your tower, equip up to 4 skills, and choose from a variety of traits and items to craft powerful builds that lead you to victory.
Why similar: Tower Defense 46.5%, Strategy 34.8%, Action 13.9%, Top-Down 4.1%, Singleplayer 0.8%
- #36 Dome Keeper
70% matchVery Positive92% of 19,233 reviews2022
Dev: BippinbitsPub: Raw Fury
Windows · Mac · Linux
Median: 4.1 hrsMean: 10.8 hrs≥1hr: 87%
Defend against waves of alien monsters in this unique roguelike action miner. Dig for resources, collect useful gadgets, and upgrade equipment to increase odds of survival – just hurry back before your dome is destroyed!
Why similar: Tower Defense 51.6%, Action 24.2%, Sci-fi 22.2%, Singleplayer 1.9%
- #37 Robowars
76% matchMixed46% of 292 reviews2014
Dev: N-Game Studios
Windows
Median: 3.0 hrsMean: 4.1 hrs≥1hr: 95%
Robowars is back on Steam! Fight off troops of droids for freedom and honor in our classical tower defense game. Lead the forces of the Solar Union to protect the peaceful planet of Praymos from the aggressive Trade Confederation.
Why similar: Tower Defense 42%, Strategy 29.2%, Sci-fi 11.2%, Action 10.1%, Top-Down 4.9%
- #38 A.I. Invasion
76% matchMostly Negative35% of 66 reviews2015
Dev: GameArt Studio GmbH
Windows
Median: 4.1 hrsMean: 7.1 hrs≥1hr: 97%
A.I. Invasion is an action-loaded top-down-shooter in a futuristic setting. The superior machines subjugated the universe. In a wide range of missions you take the role of a soldier and equip and command a team of special units to reclaim the planet system.
Why similar: Strategy 55.1%, Action 35.4%, Indie 9.4%
- #39 XENOBREAKERS: Classic Tower Defense
70% matchVery Positive86% of 83 reviews2025
Dev: Couch Potato Studios
Windows
Defend Billy and his crew on their way to the extraction zone! You have been authorized to use the defense system. Protect them from giant bugs, malfunctioning droids and more...
Why similar: Strategy 61.9%, Sci-fi 20.7%, Tower Defense 9.2%, Indie 6.6%, Singleplayer 1.7%
- #40 Black blood
73% matchMixed67% of 57 reviews2020
Dev: Arcane Games
Windows
Black blood is a mix of hardcore Tower Defense strategy and top-down shooter. Act as a defender against alien invaders, attack and destroy all their insidious plans...
Why similar: Tower Defense 45.1%, Strategy 32.8%, Action 12.7%, Top-Down 5.6%, Indie 2.9%
- #41 Defense Task Force - Sci Fi Tower Defense
73% matchMixed66% of 53 reviews2018
Dev: ChillX Ltd
Windows
Defense Task Force Featuring Large Scale Procedurally Generated Tower Defense Battles with FPS Quality Visuals and Infinite Waves. 10 tower types, with different attacks , 3 levels plus boosts. 25 Enemy alien species: Regulars, Swarmers, Racers, Cloakers, Healers, Boss Units and Spawners.
Why similar: Tower Defense 46.5%, Strategy 38.8%, Sci-fi 10.5%, Indie 4.2%
- #42 Starship Troopers: Terran Command
68% matchVery Positive87% of 11,704 reviews2022
Dev: The ArtistocratsPub: Slitherine Ltd.
Windows
Median: 3.4 hrsMean: 10.2 hrs≥1hr: 83%
Lead the Mobile Infantry in this RTS game set in the Starship Troopers film universe. Balance your army composition with a diverse set of unit types, overcome line-of-sight and line-of-fire challenges through tactical positioning, and use special abilities to smash the Arachnid hordes!
Why similar: Strategy 71.6%, Sci-fi 13.8%, Tower Defense 13.2%, Singleplayer 1.3%
- #43 Unstoppable Gorg
73% matchMostly Positive79% of 306 reviews2012
Dev: Futuremark
Windows · Mac
Median: 36 minMean: 6.3 hrs≥1hr: 40%
Defend the solar system from fearsome aliens by sending satellites into orbit in revolutionary tower defense action!
Why similar: Tower Defense 57.1%, Strategy 27%, Action 7.3%, Sci-fi 6.5%, Indie 2.1%
- #44 AI War: Fleet Command
72% matchVery Positive82% of 1,594 reviews2009
Dev: Arcen Games
Windows · Mac · Linux
Median: 2.7 hrsMean: 5.7 hrs≥1hr: 87%
"You are outgunned. You are massively outnumbered. You must win." These are your orders. Humanity has already fought its war against the machines -- and lost. AI death squads stand watch over every planet and every wormhole, the few remaining human settlements are held captive in orbiting bubbles, and the AIs have turned their...
Why similar: Strategy 79.4%, Tower Defense 10.2%, Sci-fi 8%, Indie 2.1%, Singleplayer 0.3%
- #45 No Creeps Were Harmed TD
68% matchVery Positive89% of 482 reviews2024
Dev: MinMax Games Ltd.
Windows
Median: 2.8 hrsMean: 5.5 hrs≥1hr: 74%
Employ lethal turrets, traps, and gadgets to defend against an onslaught of evolving creeps! Step into a twisted, hyper 3D, mind bending realm. Upgrade and adapt your defenses. Become a master maze crafter. Collect bizarre artifacts. Rush creeps for lucrative rewards, and succumb to greed!
Why similar: Tower Defense 46.1%, Strategy 30.6%, Sci-fi 13.5%, Action 8.7%, Singleplayer 1%
- #46 Stellar Initiative
69% matchMostly Positive77% of 390 reviews2024
Dev: Five Head Games
Windows
Median: 1.7 hrsMean: 6.6 hrs≥1hr: 66%
Stellar Initiative is a roguelike tower defense game where you land on the planet and use your orbit ship to deliver buildings and support you with fire. Complete missions, install new upgrades, discover powerful artifacts, and find the best strategy!
Why similar: Tower Defense 50.6%, Strategy 34.1%, Sci-fi 14.8%, Singleplayer 0.4%
- #47 Ancient Planet Tower Defense
71% matchVery Positive82% of 1,186 reviews2015
Dev: Moonlight Mouse
Windows · Mac
Median: 3.3 hrsMean: 7.5 hrs≥1hr: 92%
Ancient Planet is classic tower defense game. The stronghold of an ancient civilization has been invaded by hordes of alien raiders. Use powerful technologies of the Ancient and repel the attack of the enemy's armies!
Why similar: Tower Defense 67.1%, Strategy 29.9%, Indie 3%
- #48 Tower Dominion
66% matchVery Positive86% of 4,827 reviews2025
Dev: Parallel 45 Games
Windows
Median: 11.7 hrsMean: 21.5 hrs≥1hr: 90%
Build and design the terrain while defending your stronghold against alien invasion in this unique Roguelike tower defense. Choose from 30 heroes, survive enemy waves, and upgrade a variety of destructive towers to hold the line!
Why similar: Tower Defense 54.5%, Strategy 36.1%, Sci-fi 8.6%, Singleplayer 0.8%
- #49 Armed to the Gears
71% matchMixed63% of 212 reviews2020
Dev: Deonn Games
Windows
Median: 3.3 hrsMean: 3.8 hrs≥1hr: 94%
Control a fully armed Mech and fight through cyberpunk cities, military bases and industrial ruins. Capture and defend territories, build turrets and structures, and wage war against powerful enemies!
Why similar: Tower Defense 62.1%, Sci-fi 13%, Strategy 11.8%, Top-Down 6.9%, Action 5.3%
- #50 Defend Earth: Xenos Survivors
69% matchVery Positive80% of 56 reviews2023
Dev: ReijaPub: indie.io
Windows
You are Earth's last line of defense in a relentless alien invasion. Experience intense top-down roguelite action across diverse landscapes, fighting invaders with a versatile arsenal. Outsmart, outgun, and survive your foes. Every run increases the challenge - so adapt, evolve, dominate!
Why similar: Sci-fi 45%, Action 41.8%, Indie 10.5%, Singleplayer 2.7%
- #51 CARNAGE OFFERING Tower Defense
67% matchVery Positive90% of 306 reviews2023
Dev: FuturtechPub: Nova's Army
Windows
The replicator robots are back! It's 2528. The machines are increasingly infecting the planets with genetically modified monsters. Challenge them and try to stop the onslaught. Upgrade buildings and heroes, mine resources, discover technology and fight to save humanity!
Why similar: Tower Defense 55.5%, Strategy 38.9%, Action 4.4%, Indie 1.2%
- #52 Alien Marauder
70% matchMixed63% of 341 reviews2021
Dev: Vexan Studio
Windows
“Alien Marauder” is a real-time strategy game with survival and confrontation theme. In this game, you will be the leader to a treacherous alien planet, build and defend base to survive against the vexan waves. Make the right decision!
Why similar: Tower Defense 40%, Strategy 36.3%, Sci-fi 16.6%, Top-Down 6%, Singleplayer 1.1%
- #53 Planets Under Attack
71% matchMostly Positive73% of 1,241 reviews2012
Dev: Targem GamesPub: Topware Interactive
Windows · Mac
Median: 3.3 hrsMean: 10.0 hrs≥1hr: 86%
Play as humans or robots in a brand new sci-fi strategy adventure! Travel into the far reaches of space, through cleverly designed star constellations and variable game modes, conquering enemy planets using 15 combinable technologies.
Why similar: Strategy 97.6%, Sci-fi 1.3%, Indie 1.2%
- #54 SENTRY
67% matchVery Positive83% of 853 reviews2024
Dev: Fireblade Software
Windows
Median: 2.7 hrsMean: 5.2 hrs≥1hr: 70%
SENTRY is an action-defense first person shooter where you defend your spaceship against invading aliens. Plot an escape route through hostile space and battle the enemy across your vessel with the support of traps, turrets and environmental destruction.
Why similar: Tower Defense 43.4%, Strategy 31.7%, Sci-fi 13.7%, Action 10.8%, Singleplayer 0.4%
- #55 Mechs V Kaijus - Tower Defense
67% matchVery Positive84% of 529 reviews2022
Dev: Doble Punch Games
Windows
Median: 6.8 hrsMean: 13.2 hrs≥1hr: 83%
Mechs V Kaijus is an addictive hardcore tower defense gameplay. In Mechs V Kaijus you take on the role of Commander of a powerful Mechs squadron. Improve your Mech, strategically place towers and factories on the battlefield. Deploy support units on the battlefield, and save our civilization.
Why similar: Tower Defense 67.7%, Strategy 22.3%, Action 7%, Indie 2.7%, Singleplayer 0.3%
- #56 Siege of Centauri
69% matchMixed66% of 448 reviews2019
Dev: Stardock Entertainment
Windows
Median: 42 minMean: 6.0 hrs≥1hr: 44%
Defend against thousands of enemies in this explosive tower defense game. Deploy upgradable towers and unleash powerful orbital abilities as you try to protect Earth's first colony world from destruction.
Why similar: Tower Defense 45.2%, Strategy 31.3%, Sci-fi 12.1%, Action 11.4%
- #57 Gore Storm
66% matchVery Positive94% of 70 reviews2023
Dev: Gundorado
Windows
Battle massive hordes of alien monsters to secure humanity's presence on planet Gore. Upgrade your base, hire troops, and install turrets to fight back the ever growing waves of aliens.
Why similar: Tower Defense 57%, Action 22.2%, Sci-fi 13.5%, Top-Down 6.1%, Singleplayer 1.2%
- #58 Mech Fortress
63% matchVery Positive85% of 216 reviews2026
Dev: Some Sugar Studio
Windows
Mech Fortress is a sci-fi tower defense game where each turret has unique mechanics. You can freely place them on a 5×5 grid, and your goal is to eliminate all enemies!
Why similar: Tower Defense 52.1%, Strategy 34.1%, Sci-fi 10.1%, Top-Down 3.1%, Singleplayer 0.5%