Co-operative multiplayer game and complete code base available for free.
User reviews:
Recent:
Very Positive (223 reviews) - 94% of the 223 user reviews in the last 30 days are positive.
Overall:
Overwhelmingly Positive (14,725 reviews) - 95% of the 14,725 user reviews for this game are positive.
Release Date: Jul 19, 2010

Sign in to add this item to your wishlist, follow it, or mark it as not interested

Play Alien Swarm

Free Game

 

Recommended By Curators

"(Free) Co-operative multiplayer game and complete code base available for free. Made by Valve."

About This Game

Alien Swarm is a game and Source SDK release from a group of talented designers at Valve who were hired from the Mod community.
Available free of charge, the game thrusts players into an epic bug hunt featuring a unique blend of co-op play and squad-level tactics. With your friends, form a squad of four distinct IAF Marine classes. Plan your attack using an unlockable arsenal of weapons with countless loadout configurations against a wide variety of aliens. Blaze your way through an overrun, off-world colony, eradicating the alien infestation in environments ranging from the icy planet's surface, to a subterranean lava-flooded mining facility.
Along with the game get the complete code base for Alien Swarm that features updates to the Source engine as well as the SDK. Alien Swarm adds 3rd person camera, depth of field, improved dynamic shadows and a wide variety of gameplay additions to the Source engine.
  • Tactical, 4 player co-op action game with a top-down perspective
  • Complete game code and mod tools
  • Unlock persistent items by gaining levels
  • Over 40 weapons and equipment with countless loadout configurations
  • 4 unique classes and 8 unique characters
  • Matchmaking, Steam Cloud, Steam Stats
  • 64 achievements
  • Tile-based map generation tool
  • Powered by Source and Steam

System Requirements

    Minimum:
    • OS: Windows® 7 / Vista / Vista64 / XP
    • Processor: Pentium 4 3.0GHz
    • Memory: 1 GB for XP / 2GB for Vista
    • Graphics: DirectX 9 compatible video card with 128 MB, Shader model 2.0. ATI X800, NVidia 6600 or better
    • Hard Drive: At least 2.5 GB of free space
    • Sound: DirectX 9.0c compatible sound card
    Recommended:
    • OS: Windows® 7 / Vista / Vista64 / XP
    • Processor: Intel core 2 duo 2.4GHz
    • Memory: 1 GB for XP / 2GB for Vista
    • Graphics: DirectX 9 compatible video card with Shader model 3.0. NVidia 7600, ATI X1600 or better
    • Hard Drive: At least 2.5 GB of free space
    • Sound: DirectX 9.0c compatible sound card
Customer reviews
Customer Review system updated Sept. 2016! Learn more
Recent:
Very Positive (223 reviews)
Overall:
Overwhelmingly Positive (14,725 reviews)
Review Type


Purchase Type


Language


Display As:


(what is this?)
7,346 reviews match the filters above ( Overwhelmingly Positive)
Most Helpful Reviews  In the past 30 days
12 of 12 people (100%) found this review helpful
2 people found this review funny
Recommended
55.9 hrs on record
Posted: September 5
Alien Swarm is a fantastic, top down co-op shooter which deserves more recognition than it got. While it only has a short campaign (which can be played with up to four friends), there are many addon campaigns and mods online, which make a substantial difference to the experience.

Best played with friends, there is still an active community around this game, so finding other players shouldn't be too difficult. The standard campaign provides decent challenge and entertainment, especially when you increase the difficulty.

Best part? Its completely free... you have nothing to lose by giving it a try.
Was this review helpful? Yes No Funny
11 of 12 people (92%) found this review helpful
5 people found this review funny
Recommended
3.3 hrs on record
Posted: August 31
Valve did a thing its pretty cool
Was this review helpful? Yes No Funny
7 of 8 people (88%) found this review helpful
Recommended
43.4 hrs on record
Posted: September 2
This game shouldn't be dead
Was this review helpful? Yes No Funny
4 of 4 people (100%) found this review helpful
4 people found this review funny
Recommended
3.2 hrs on record
Posted: August 29
The one game my girlfriend can beat me in :/
Was this review helpful? Yes No Funny
2 of 2 people (100%) found this review helpful
2 people found this review funny
Recommended
14.9 hrs on record
Pre-Release Review
Posted: September 17
I kicked my friend in the back of the head for failing the team and it sent him flying out the map
Was this review helpful? Yes No Funny
2 of 2 people (100%) found this review helpful
Recommended
35.6 hrs on record
Pre-Release Review
Posted: September 26
Atmospheric:
The aliens in the vents make their noises,
and the motion scanner bleeps kep you on the edge of your seat,
and make you fall off when you wander into an ambush.

Hard:
This game requires tactical eye and teamwork
between you and your squadmates.
You must play smart and look after each other,
because that is one less gun in the game,
and your chances of survival become very slim at best.

Fair:
If you get eaten it means 'you dun goofed up'.
Tie game doesn't resort to cheating.
The alien AI is quite smart and they can
easily outsmart you if you aren't paying attention.

Fun?:
Alone:
It can be fun, if you are skilled enough
and are used to RTS games. But it can be
frustratingly hard solo.

With 1-3 friends:
Two-player game is quite fun, but this game shines
with a full squad of human players as you struggle
on towards your objective, counting on each other,
and hoping you can pull it off without any hirches,
and that everyone survives.

Of course, this is where friendly fire comes into play.
'Friendly fire is not'. You WILL take damage from squadmates.
In the beginning you are more likely to die from
a squadmate trying to shoot an alien trough you
than the actual alien.

In this game players need
good communication and discipline to make it trough
while still being ready to take action at any time.
This doesn't mean this game is meant for twitch players.
I'd say it is quite the opposite.
You can survive by playing the game as a twitch action shooter,
but you can negate need for reflexes with some
tactical awareness and being in the right place at the right time
and anticipating the enemy.

The only negative things I can say about this game is
that there aren't many enemy types and the
main campaign included is a little short.
I really do wish they added more official maps to this game.

Overall?
This game is hard. But incredibly rewarding. And free.
Definitely worth adding to your Steam library and giving it a spin.
So what are you still waiting for?
Click that "Play Game" button already!

LOCK AND LOAD!

P.S. Did I mention you also get a free hat for Team Fortress 2?
Was this review helpful? Yes No Funny
2 of 2 people (100%) found this review helpful
Recommended
0.6 hrs on record
Posted: August 31
Outta all the free 2 play games i played for tf2 hats, i think alien swarm was the most pleasing one. I would play alien swarm again for sure. Definately play this game if you want a decent free 2 play game or a really old tf2 hat.
Was this review helpful? Yes No Funny
1 of 1 people (100%) found this review helpful
Recommended
8.2 hrs on record
Posted: September 18
It's a good game !
Was this review helpful? Yes No Funny
1 of 1 people (100%) found this review helpful
Recommended
20.6 hrs on record
Posted: September 17
great game, still is holding up in the graphics department since 2010. best played with a friend who screams at everything and over all leveling to max level is satisfying.
Was this review helpful? Yes No Funny
1 of 1 people (100%) found this review helpful
Recommended
4.9 hrs on record
Posted: September 16
10/10 would frag teammates again

Wish they added more campaigns
Was this review helpful? Yes No Funny
Recently Posted
(G.E.W.P) GamerPichu
3.9 hrs
Posted: September 28
Good Game.
Helpful? Yes No Funny
n'Zapador
19.6 hrs
Posted: September 27
Not something I would play solo or with randoms, but with a couple of friends it is a very enjoyable game. Easy to get into, difficult to master.
Helpful? Yes No Funny
Kanjiklub_Member
1.1 hrs
Posted: September 27
It's a amazing game that is completely FREE! It's a third person shooter where you enter what I assume is a gaint space station over run with alien parasites. Your job is to run through the area you and your fellow marines are designated to search for survivors and to find out what happened. It's your chose if you want to kill all of them or run away with your marines and seal a door behind you for safety... until they break through the door... and there are probably aliens in the room with you. There are four class with two different option for all four. There's the Medic, Technical Specialists, Special Weapons and the Officer. The Officer gives buffs to his fellow marines. The Medic uses a singluar or area for healing others. The Special Weapons use big and powerful guns to deal with the swarm, and high health making him good for playing defence. The Technical Specialists has the ability to hack now this may not sound good, but you must have him on almost every mission! Now that all the stuff that makes the classes different from each other is out of the way. We can talk about unlocking different weapons. So you unlike weapons by playing multiplayer and leveling up at the same time. The only bad thing that I can think of about this game is playing online without playing with your friends because their aren't many people playing online without friends. So you have to play single player and do the same level over and over again. Also in multiplayer there are more variety of aliens start appearing as you make your way through the campaign.

Hopeful people who see this reveiw may start playing online with out friends and we can rebuild the community! Also if you came here for the Team Fortress 2 hat, rebuilding the community will help you with that!
Helpful? Yes No Funny
Lolle man
90.5 hrs
Posted: September 27
my first ever game on steam
nostalgia is real
Helpful? Yes No Funny
Bullclip
13.4 hrs
Posted: September 26
One of the better games i've played 9/10
Helpful? Yes No Funny
the.waves.of.time
10.5 hrs
Posted: September 26
Really fun and well optimized co-op game. To be honest this is the best co-op game I have come across for a long time (if not the best period)

Pros:
- Surprisingly good graphics – I expected something with really bad graphics but after setting qhd resolution and all the shadows on max
- Great optimization – game is really fluent no fps drops, not a lot of lags
- Almost no bugs (we only once encountered immortal alien who killed every one of us)
- Variety of tactics – every mission is different you cannot just smash every mission with one weapons set or one character, you need to think a lot and cooperate a lot
- Difficulty – you need to be focused and really cooperate with your team members – if you will be just rushing ahead with no plan you are going to go down and you will do it fast
- Weapons and equipment variety
- Levelling – you cannot really go op what is a good thing and levelling is a good way to introduce new equipment
- Its free and I have not seen any micro-payments

Cons:
- Way too short – just one campaign with few missions – joke – and most of the online fan-missions are nowhere near as good as the first campaign (Poorly designed and 70% of them are: survive 7 waves)
- Some of the weapons and equipment are way too weak and useless and some are really strong (example: slow high damage rifles are not very useful whereas minigun, flamer and sentry gun are really powerful\
- Quickly gets boring as not enough missions is supplied with a game

All in all I would recommend this game to anyone who is looking for a good coop to play with friends and a great time-killer. I cannot really downrate it because it is too short as it is free but I would gladly buy it for lets say fiver.
Helpful? Yes No Funny
GamesFrontline
5.5 hrs
Posted: September 25
For Free ? WHOA!!
Helpful? Yes No Funny
Nefalol
31.7 hrs
Posted: September 25
This game... It's just a great game, but It does lack some features maybe they can release alien swarm 2 or something like that. The only thing I want out of this game is... Longer Campaigns yup.. and that's It. I rate it a 9.5/10
Helpful? Yes No Funny
WRK! ♛☠10001011101☜(˚▽
5.8 hrs
Posted: September 24
+PT-BR+
Não tenho muito a falar sobre,só digo que é bom e divertido,além de desbloquear um chapéu no TF2(e não é dificil)

+ENG+
I don't have much to say,i'ts good and fun,it also unlocks a TF2 hat(it's not hard)
Helpful? Yes No Funny