Games like Fortified on Steam

For those who prefer not to search, lists of the most played, top deals and best free games like Fortified are available at the bottom of the page.

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Cortex Command Choose between different factions, with their own set of expendable soldiers, mechas, and weapons. Protect your brain, mine gold, and destroy the enemy cortex in his bunker complex!

Similarity 50%
Price -96% 0.89€
Rating 7.0
Release 28 Sep 2012
Epigenesis Epigenesis is an online multiplayer sports/FPS game in which two sides are locked in a never-ending fight for world domination by playing ball.In this non-lethal ballgame of the future, players leap across platforms suspended high up in the air trying to get a ball located in the middle of the arena and score goals against their...

Similarity 50%
Price Free to play
Rating 6.4
Release 01 Aug 2014
Alien Swarm Co-operative multiplayer game and complete code base available for free.

Similarity 50%
Price Free to play
Rating 9.3
Release 19 Jul 2010
ROCKETSROCKETSROCKETS ROCKETS fire ROCKETS at ROCKETS in this action-arcade, arena-combat, gorgeous festival-of-fireworks! It's dogfighting meets figure-skating in space with local multiplayer and single-player fast-paced action modes plus a ZEN MODE where ROCKETS learn to LOVE.

Similarity 50%
Price -87% 0.93€
Rating 7.1
Release 01 May 2015
WIN THE GAME: DO IT! WIN THE GAME: DO IT! - is a hardcore game. Try to finish the game without spending your nerves.

Similarity 50%
Price 0.99€
Rating 6.1
Release 02 May 2018
Of Guards And Thieves Of Guards and Thieves is a multiplayer stealth game in which high-powered guards face off against fast and elusive thieves in a contest of wits. Outsmarting the enemy and shooting your way through to the goal are equally valid strategies. Simple rules, emergent gameplay and high replayability.

Similarity 50%
Price Free to play
Rating 8.3
Release 16 Jul 2014
Dave's Fun Algebra Class: Remastered Dave's Fun Algebra Class: Remastered is a strategy-based indie game inspired by Baldi's Basics, featuring chaotic and intense gameplay mixed with an old-school psychedelic artstyle. Solve math problems, meet Dave's friends, and uncover the secrets of Dave's school.

Similarity 50%
Price Free to play
Rating 8.3
Release 03 Apr 2024
You have a drunk friend What will you play if you have a very drunk friend? A warm hearted angel? Or an evilbad guy?You may find answer in this fun weird game. Try exploring in the room and figure out how to sober up your friend, may it's not only just one solution,though,never hurt friend,and never do evil!

Similarity 50%
Price 0.79€
Rating 6.1
Release 09 Nov 2018
Mouse (Sneaking) In this runner game, you play as a mouse who has stolen cheese as much as you can.

Similarity 50%
Price 0.99€
Rating 7.8
Release 16 Jan 2018
Kings of Kung Fu Inspired by classic Kung Fu films, this passion fueled fighter provides fun 1 vs. 1 gameplay for gamers of all skill levels. Take on the role of one of 14 martial arts stunt masters as you fight to show your style cannot be beat. Fight it out in the Single Player Arcade Mode or Local Two Player VS. Matches.

Similarity 50%
Price -96% 0.44€
Rating 6.3
Release 25 Jun 2015
SpyParty SpyParty is a competitive espionage game about subtle human behavior. A Spy hides in plain sight at a fancy cocktail party, trying to accomplish missions while blending in with the other guests, while a Sniper with a single bullet looks inward, searching for the Spy.

Similarity 50%
Price 24.50€
Rating 7.6
Release 12 Apr 2018
Kick Ass Commandos Lock and Load! It's time to Kick-Ass. Grab your machine gun, flamethrower, rocket launcher, and grenades. Assault the enemy base and free commandos to join your team while you destroy everything in sight. Make your way through enemy bunkers to rescue your comrades, and kill everyone you encounter!

Similarity 50%
Price -92% 0.56€
Rating 8.6
Release 17 Nov 2016
Gears 5 From one of gaming’s most acclaimed sagas, Gears is bigger than ever. With all-out war descending, Kait Diaz breaks away to uncover her connection to the enemy and discovers the true danger to Sera – herself.

Similarity 50%
Price 29.99€
Rating 6.9
Release 09 Sep 2019
Satellite Reign Satellite Reign is a real-time, class-based strategy game, set in an open-world cyberpunk city. You command a group of 4 agents through rain-soaked, neon-lit streets, where the law is the will of mega-corporations.

Similarity 50%
Price -92% 2.22€
Rating 7.0
Release 27 Aug 2015
Earth Defense Force: Insect Armageddon Thousands of giant insects and aliens once again ravage the earth, and only the Earth Defense Force can stop them.

Similarity 50%
Price 9.99€
Rating 8.3
Release 14 Dec 2011
Sea Salt Sea Salt is a dark fantasy reverse horror action-strategy game where you play as the nightmarish force of Dagon by controlling and growing a horde of minions.

Similarity 49%
Price -95% 0.88€
Rating 7.5
Release 17 Oct 2019
Karateka From PRINCE OF PERSIA creator Jordan Mechner, the original side-scrolling karate classic comes to Steam with art by Jeff Matsuda (The Batman) and music by Grammy-winning composer Christopher Tin (CIVILIZATION IV).

Similarity 49%
Price -78% 0.89€
Rating 6.7
Release 03 Dec 2012
Voxel Turf Voxel Turf is a block based urban sandbox. Build cities, blow up buildings, complete missions or fight for territory. Build a real estate empire, or perhaps just drive around and blow stuff up. Its your choice!

Similarity 49%
Price 7.99€
Rating 8.2
Release 13 Sep 2017
Zombie Army Trilogy The cult horror shooter series comes to an apocalyptic conclusion with an epic new third chapter, a heart-pumping new horde mode, and remastered editions of the best-selling Nazi Zombie Army 1 & 2.

Similarity 49%
Price -92% 3.69€
Rating 8.5
Release 06 Mar 2015
Nefarious Play as the villain in Nefarious! An action platformer where you globe hop between several kingdoms kidnapping princesses who alter gameplay in unique ways. Then thwart various heroes in reverse boss fights, recreated iconic battles where you control the boss.

Similarity 49%
Price 14.99€
Rating 7.9
Release 23 Jan 2017
Northend Tower Defense Jump into a realtime strategy, action filled battlefield, deploy relentless soldiers, unlock powerful troops and vehicles, upgrade your army, decimate the enemy. If that's not enough, jump into a chaotic Zombie mode, with traps, fun upgrades, and a new gameplay!

Similarity 49%
Price -94% 0.51€
Rating 7.4
Release 04 Sep 2024
Prime World: Defenders Fight off hordes of monstrous mutants created from a strange cataclysmic event in the new tower defense game, Prime World: Defenders. Join a group of exile treasure hunters who have ventured into the capital of an ancient empire, vast with mystery and danger.

Similarity 49%
Price 8.99€
Rating 7.2
Release 05 Jun 2013
No Heroes Here No Heroes Here is a frantic co-op game for 1 to 4 players, available in local and online modes. Craft and use several items effectively whilst coordinating your ragtag band of non-heroes to defend castles and survive! ...Oh, as well as saving the Kingdom in the meantime!

Similarity 49%
Price 12.49€
Rating 8.4
Release 02 Oct 2017
Hacktag Hacktag is a fast-paced two-player co-op stealth-game with unique asymmetric gameplay. Play as the stealth Agent in the field or as the virtually-infiltrated Hacker and work together to carry out espionage missions where nothing goes as expected!

Similarity 49%
Price 9.99€
Rating 6.4
Release 14 Feb 2018

Most played games like Fortified on Steam

Take a look at the top games like Fortified that are currently attracting the largest player bases on the Steam platform, as of June 16th 2025.

1. Bloons TD 6

Similarity 51% The Bloons are back and better than ever! Get ready for a massive 3D tower defense game designed to give you hours and hours of the best strategy gaming available. Bloons TD 6 is a tower defense, strategy and multiplayer game developed and published by Ninja Kiwi. Released on December 17th 2018 has received 353,960 reviews of which 344,269 were positive and 9,691 were negative resulting in an impressive rating of 9.6 out of 10. The game has hit the top spot as the #1 most played game like Fortified, thanks to its 9,200 peak concurrent players over the last day.
9.6
344,269
9,691

9,200
players

2. Orcs Must Die! Deathtrap

Similarity 72% Orcs Must Die! Deathtrap combines chaotic third-person combat with devious trap-laying strategy. Enjoy endless replayability as your War Mage grows stronger through roguelite progression. Repel relentless orc hordes solo or with up to 4 players. Orcs Must Die! Deathtrap is a tower defense, third-person shooter and co-op game developed and published by Robot Entertainment. Released on January 28th 2025 has received 3,338 reviews of which 2,388 were positive and 950 were negative resulting in a rating of 7.0 out of 10. While seeing 535 players online at once in the last 24 hours, this game is currently ranked #2 among games like Fortified based on player count.
7.0
2,388
950

535
players

3. The Perfect Tower II

Similarity 53% The Perfect Tower II is a mix between an incremental and a tower defense game. Build a town, manage resources and explore a variety of mini-games and tons of upgrades. Fully automate your game and watch numbers going up! The Perfect Tower II is a strategy, idler and tower defense game developed and published by Fire Sword Studios. Released on February 26th 2021 has received 3,639 reviews of which 3,201 were positive and 438 were negative resulting in a rating of 8.5 out of 10. While seeing 526 players online at once in the last 24 hours, this game is currently ranked #3 among games like Fortified based on player count.
8.5
3,201
438

526
players

4. Bloons TD Battles 2

Similarity 57% From the creators of Bloons TD6... Bloons TD Battles 2 is a brand new installment of the top-rated head-to-head tower defense game. Gather your Hero, choose your team of powerful Monkey Towers, and prepare to battle one on one against other players and relentless waves of Bloons! Bloons TD Battles 2 is a free to play, tower defense and multiplayer game developed and published by Ninja Kiwi. Released on November 30th 2021 has received 32,320 reviews of which 27,193 were positive and 5,127 were negative resulting in a rating of 8.3 out of 10. With 477 concurrent players in the last 24 hours, the game currently holds the #4 spot among the most played games like Fortified.
8.3
27,193
5,127

477
players

5. Gears 5

Similarity 50% From one of gaming’s most acclaimed sagas, Gears is bigger than ever. With all-out war descending, Kait Diaz breaks away to uncover her connection to the enemy and discovers the true danger to Sera – herself. Gears 5 is a action, adventure and third-person shooter game developed by The Coalition and published by Xbox Game Studios. Released on September 09th 2019 has received 23,309 reviews of which 16,400 were positive and 6,909 were negative resulting in a rating of 6.9 out of 10. With 371 concurrent players in the last 24 hours, the game currently holds the #5 spot among the most played games like Fortified.
6.9
16,400
6,909

371
players

6. Bloons TD Battles

Similarity 58% Go head to head with other players in a Bloon-popping battle for victory. From the creators of best-selling Bloons TD 5, this all new Battles game is specially designed for multiplayer combat, featuring the ability to control bloons directly and send them charging past your opponent's defenses. Bloons TD Battles is a free to play, tower defense and multiplayer game developed and published by Ninja Kiwi. Released on April 20th 2016 has received 29,096 reviews of which 26,414 were positive and 2,682 were negative resulting in a rating of 8.9 out of 10. With 275 concurrent players in the last 24 hours, the game currently holds the #6 spot among the most played games like Fortified.
8.9
26,414
2,682

275
players

7. Bloons Monkey City

Similarity 57% Create, upgrade, and customize your very own Bloons Monkey City in this groundbreaking blend of city building and tower defense awesomeness! Bloons Monkey City is a free to play, strategy and action game developed and published by Ninja Kiwi. Released on April 10th 2020 has received 6,222 reviews of which 5,676 were positive and 546 were negative resulting in a rating of 8.8 out of 10. With 272 concurrent players in the last 24 hours, the game currently holds the #7 spot among the most played games like Fortified.
8.8
5,676
546

272
players

8. Cube Racer

Similarity 55% Cube Racer is a round based multiplayer racing game with cubes. Every round, all players race against each other to the finish line. Before every round, the players get to build one or more obstacles on the map. In the next round, all players have to pass all the obstacles, which have been built yet. Cube Racer is a indie, action and casual game developed and published by Simon Blasen. Released on October 30th 2017 has received 1,980 reviews of which 1,791 were positive and 189 were negative resulting in a rating of 8.6 out of 10. With 223 concurrent players in the last 24 hours, the game currently holds the #8 spot among the most played games like Fortified.
8.6
1,791
189

223
players

9. Bloons TD 5

Similarity 64% Five-star tower defense with unrivaled depth and replayability. The Bloons are back in full HD glory and this time they mean business! Build awesome towers, choose your favorite upgrades, hire new Special Agents, and pop every last invading Bloon in the most popular tower defense series in history. Bloons TD 5 is a tower defense, strategy and co-op game developed and published by Ninja Kiwi. Released on November 19th 2014 has received 11,545 reviews of which 10,926 were positive and 619 were negative resulting in an impressive rating of 9.2 out of 10. With 180 concurrent players in the last 24 hours, the game currently holds the #9 spot among the most played games like Fortified.
9.2
10,926
619

180
players

10. Creeper World 3: Arc Eternal

Similarity 50% 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. Creeper World 3: Arc Eternal is a tower defense, strategy and indie game developed and published by Knuckle Cracker. Released on March 27th 2014 has received 4,647 reviews of which 4,487 were positive and 160 were negative resulting in an impressive rating of 9.3 out of 10. With 172 concurrent players in the last 24 hours, the game currently holds the #10 spot among the most played games like Fortified.
9.3
4,487
160

172
players

Best deals on games like Fortified on Steam

Discover fantastic savings with the best discounts on a variety of games like Fortified available on Steam right now, updated on June 16th 2025. Looking for even more deals? Use the search filters to explore a wider range of discounted games like Fortified.

1. Spin Rush

Similarity 50% Spin Rush is 2D arcade game, where you have to collect dots and match colors. Spin Rush is a indie, casual and action game developed by EGAMER and published by SA Industry. Released on September 16th 2016 has received 583 reviews of which 442 were positive and 141 were negative resulting in a rating of 7.2 out of 10. Featuring a massive 99% discount, this game currently holds the #1 spot in the best deals for games like Fortified.
7.2
442
141

-99% 29.99€ 0.44€

2. Neon Space 2

Similarity 59% Neon Space 2 is a highly anticipated sequel to Neon Space. The game kept all the elements from his predecessor, but at the same time the visuals received a major improvement. Neon Space 2 is a action, indie and casual game developed by EGAMER and published by SA Industry. Released on July 26th 2016 has received 422 reviews of which 298 were positive and 124 were negative resulting in a rating of 6.7 out of 10. Thanks to its incredible 99% discount, this game is now the #2 best deal in games like Fortified.
6.7
298
124

-99% 29.99€ 0.32€

3. HERO DEFENSE

Similarity 82% CREEPS CRUMBLE. HEROES RISE. Command a team of renegade heroes and impale, slash, tear and burn through legions of undead hell-bent on world domination. Your mission: to defeat the world’s most powerful vampire, Count Necrosis. HERO DEFENSE is a tower defense, strategy and indie game developed by Happy Tuesday and published by Headup. Released on May 31st 2016 has received 747 reviews of which 471 were positive and 276 were negative resulting in a rating of 6.1 out of 10. Thanks to its incredible 99% discount, this game is now the #3 best deal in games like Fortified.
6.1
471
276

-99% 29.99€ 0.56€

4. X-Morph: Defense

Similarity 82% 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. X-Morph: Defense is a tower defense, strategy and action game developed by and published by Exor Studios. Released on August 30th 2017 has received 3,823 reviews of which 3,506 were positive and 317 were negative resulting in a rating of 8.8 out of 10. Currently offered at a significant 98% discount, this title has earned the #4 position in the best deals for games like Fortified.
8.8
3,506
317

-98% 19.99€ 0.54€

5. Embr

Similarity 55% Fight fires for fun and profit in this unpredictable and frantic multiplayer game. Team up with friends, take on daily challenges and climb to the top of the corporate firefighting ladder. More than one way to become a hero! Embr is a action, simulation and strategy game developed by Muse Games and published by Curve Games. Released on September 23rd 2021 has received 1,961 reviews of which 1,704 were positive and 257 were negative resulting in a rating of 8.3 out of 10. Currently offered at a significant 98% discount, this title has earned the #5 position in the best deals for games like Fortified.
8.3
1,704
257

-98% 19.99€ 0.57€

6. DG2: Defense Grid 2

Similarity 71% Setting the bar as the definitive tower defense game, Defense Grid 2 introduces new worlds and threats to test your tower placement strategies. With a bold new look and the addition of new game modes, player-versus-player and multiplayer co-op, every play brings fun new opportunities and challenges. DG2: Defense Grid 2 is a strategy, tower defense and indie game developed by Hidden Path Entertainment and published by Hidden Path Entertainment and 505 Games. Released on September 23rd 2014 has received 3,163 reviews of which 2,723 were positive and 440 were negative resulting in a rating of 8.3 out of 10. Currently offered at a significant 98% discount, this title has earned the #6 position in the best deals for games like Fortified.
8.3
2,723
440

-98% 12.49€ 0.26€

7. Police Stories

Similarity 51% A fresh take on top-down shooters with an emphasis on tactics that forces you to make split second decisions. Neutralize criminals, rescue civilians and defuse bombs in Single Player mode or Co-op. And remember - shooting first is not an option! Police Stories is a action, strategy and co-op game developed and published by HypeTrain Digital. Released on September 19th 2019 has received 8,701 reviews of which 7,406 were positive and 1,295 were negative resulting in a rating of 8.3 out of 10. Currently offered at a significant 98% discount, this title has earned the #7 position in the best deals for games like Fortified.
8.3
7,406
1,295

-98% 19.99€ 0.53€

8. Deathtrap

Similarity 75% Deathtrap is a Tower Defense game with strong action-RPG elements, a game of vicious tricks, killing machines, rotating blades and splattering blood. Deathtrap is a tower defense, rpg and action game developed and published by NeocoreGames. Released on February 04th 2015 has received 2,194 reviews of which 1,842 were positive and 352 were negative resulting in a rating of 8.1 out of 10. Currently offered at a significant 98% discount, this title has earned the #8 position in the best deals for games like Fortified.
8.1
1,842
352

-98% 19.99€ 0.49€

9. The Blackout Club

Similarity 56% The Blackout Club is a first-person co-op horror game centered around a group of teenage friends investigating a monstrous secret beneath the skin of their small town. 1-4 players explore procedurally-generated missions against a fearsome enemy you can only see with your eyes closed. The Blackout Club is a horror, co-op and indie game developed and published by Question. Released on July 29th 2019 has received 2,847 reviews of which 2,214 were positive and 633 were negative resulting in a rating of 7.5 out of 10. Currently offered at a significant 98% discount, this title has earned the #9 position in the best deals for games like Fortified.
7.5
2,214
633

-98% 28.99€ 0.68€

10. Rock of Ages 3: Make & Break

Similarity 54% Competitive tower defense meets arcade action and gets rolled up with ACE Team's quirky, Monty Python-esque humor into one giant, creative game for the ages. This time around, you can even make your own levels! Rock of Ages 3: Make & Break is a strategy, action and comedy game developed by ACE Team and Giant Monkey Robot and published by Maximum Entertainment and 3goo. Released on July 21st 2020 has received 1,436 reviews of which 1,075 were positive and 361 were negative resulting in a rating of 7.2 out of 10. Currently offered at a significant 98% discount, this title has earned the #10 position in the best deals for games like Fortified.
7.2
1,075
361

-98% 29.99€ 0.72€

Free games like Fortified on Steam

Check out this fantastic list of free-to-play games like Fortified you can enjoy on Steam right now, updated on June 16th 2025. Looking for even more free titles? Use the search filters to explore a wider range of free to play games like Fortified.

1. The Perfect Tower II

Similarity 53% The Perfect Tower II is a mix between an incremental and a tower defense game. Build a town, manage resources and explore a variety of mini-games and tons of upgrades. Fully automate your game and watch numbers going up! The Perfect Tower II is a strategy, idler and tower defense game developed and published by Fire Sword Studios. Released on February 26th 2021 has received 3,639 reviews of which 3,201 were positive and 438 were negative resulting in a rating of 8.5 out of 10. With 526 active players enjoying it for free, this strategy game has reached the #1 spot among the top free games like Fortified.
8.5
3,201
438

526
players

2. Bloons TD Battles 2

Similarity 57% From the creators of Bloons TD6... Bloons TD Battles 2 is a brand new installment of the top-rated head-to-head tower defense game. Gather your Hero, choose your team of powerful Monkey Towers, and prepare to battle one on one against other players and relentless waves of Bloons! Bloons TD Battles 2 is a free to play, tower defense and multiplayer game developed and published by Ninja Kiwi. Released on November 30th 2021 has received 32,320 reviews of which 27,193 were positive and 5,127 were negative resulting in a rating of 8.3 out of 10. Thanks to its free to play tag and a daily player base of 477, this game has secured the #2 spot in the ranking of free games like Fortified.
8.3
27,193
5,127

477
players

3. Bloons TD Battles

Similarity 58% Go head to head with other players in a Bloon-popping battle for victory. From the creators of best-selling Bloons TD 5, this all new Battles game is specially designed for multiplayer combat, featuring the ability to control bloons directly and send them charging past your opponent's defenses. Bloons TD Battles is a free to play, tower defense and multiplayer game developed and published by Ninja Kiwi. Released on April 20th 2016 has received 29,096 reviews of which 26,414 were positive and 2,682 were negative resulting in a rating of 8.9 out of 10. Thanks to its free to play tag and a daily player base of 275, this game has secured the #3 spot in the ranking of free games like Fortified.
8.9
26,414
2,682

275
players

4. Bloons Monkey City

Similarity 57% Create, upgrade, and customize your very own Bloons Monkey City in this groundbreaking blend of city building and tower defense awesomeness! Bloons Monkey City is a free to play, strategy and action game developed and published by Ninja Kiwi. Released on April 10th 2020 has received 6,222 reviews of which 5,676 were positive and 546 were negative resulting in a rating of 8.8 out of 10. Attracting a solid base of 272 players due to its free access, this strategy game has achieved the #4 position in the best free games like Fortified.
8.8
5,676
546

272
players

5. Cube Racer

Similarity 55% Cube Racer is a round based multiplayer racing game with cubes. Every round, all players race against each other to the finish line. Before every round, the players get to build one or more obstacles on the map. In the next round, all players have to pass all the obstacles, which have been built yet. Cube Racer is a indie, action and casual game developed and published by Simon Blasen. Released on October 30th 2017 has received 1,980 reviews of which 1,791 were positive and 189 were negative resulting in a rating of 8.6 out of 10. Attracting a solid base of 223 players due to its free access, this strategy game has achieved the #5 position in the best free games like Fortified.
8.6
1,791
189

223
players

6. Ninja Kiwi Archive

Similarity 55% Enjoy some of the best loved Flash games of the past in this awesome time capsule of over 60 Ninja Kiwi classics. Experience a piece of history and play the original Flash games that spawned the worldwide phenomenon of Bloons TD. Ninja Kiwi Archive is a casual, arcade and strategy game developed and published by Ninja Kiwi. Released on July 08th 2020 has received 5,439 reviews of which 5,107 were positive and 332 were negative resulting in an impressive rating of 9.1 out of 10. Attracting a solid base of 160 players due to its free access, this strategy game has achieved the #6 position in the best free games like Fortified.
9.1
5,107
332

160
players

7. Bloons Adventure Time TD

Similarity 58% Defend Ooo from the Bloon invasion in this epic tower defense crossover. Bloons Adventure Time TD is a strategy, action and tower defense game developed and published by Ninja Kiwi. Released on January 16th 2019 has received 4,302 reviews of which 3,743 were positive and 559 were negative resulting in a rating of 8.4 out of 10. The game currently holds the #7 spot among the most played free games like Fortified.
8.4
3,743
559

89
players

8. Nova-Life: Amboise

Similarity 50% Nova-Life: Amboise is a multiplayer role-play simulation video game. Create your character and start your second life! Nova-Life: Amboise is a simulation, indie and action game developed and published by TeamNova. Released on April 22nd 2019 has received 1,548 reviews of which 1,219 were positive and 329 were negative resulting in a rating of 7.6 out of 10. The game currently holds the #8 spot among the most played free games like Fortified.
7.6
1,219
329

27
players

9. Alien Swarm

Similarity 50% Co-operative multiplayer game and complete code base available for free. Alien Swarm is a free to play, co-op and action game developed and published by Valve. Released on July 19th 2010 has received 21,274 reviews of which 20,179 were positive and 1,095 were negative resulting in an impressive rating of 9.3 out of 10. The game currently holds the #9 spot among the most played free games like Fortified.
9.3
20,179
1,095

26
players

10. Zombie Defense

Similarity 57% A modern hybrid of the classic RTS and modern Tower Defense. Recruit soldiers, place them on slots and let them shoot incoming waves of zombies by their own. Order supplies, throw grenades, order airstrikes and many more... Perfect mix of strategy, tactics and micromanagement. Zombie Defense is a free to play, zombies and tower defense game developed and published by Home Net Games. Released on September 30th 2016 has received 2,157 reviews of which 1,811 were positive and 346 were negative resulting in a rating of 8.1 out of 10. The game currently holds the #10 spot among the most played free games like Fortified.
8.1
1,811
346

18
players