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.

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Blog RSS Feed Post news Report abuse Latest News: Happy Birthday, Swarm Director 2!

About Swarm Director 2 with 0 comments by BenLubar on Jul 3rd, 2015

v3 Full

You could say that Alien Swarm is like Left 4 Dead because it has 4-player co-op and it’s made by Valve. But then you could say Left 4 Dead is like Call of Duty because they both contain guns and zombies.

The fact is, you can’t really compare games using their surface appearance. Alien Swarm is the only free non-competitive Valve game. Alien Swarm brought the Source SDK and Source modding in general to people who had never purchased a Valve game before.


Sadly, Alien Swarm was all but abandoned by Valve, with no updates to the core game since 2010, the year the game was released. But because it’s free and open to modding, anyone can continue from where Valve left off. Or, for that matter, take it in a completely different direction. For example, Lambda Wars is a Half-Life 2-themed real time strategy game.

But I’m not here to talk about total conversion mods. And you’re not here to read about them. Let’s talk Alien Swarm.

Although Swarm Director 2 improves gameplay on several official and custom maps, it does not contain its own content. Instead, a list of suggested custom campaigns and a place to download each is included with the mod, and fixes for bugs in those maps are written in C++ as part of the mod’s code. Additionally, if you have Reactive Drop installed, Swarm Director 2 will load the Extermination, Operation Cleansweep, and Paranoia campaigns from it.

Operation CleansweepParanoia

We also add new features for mappers, the biggest example being a new pair of entities that can be used to make ceilings, bridges, or basically anything that would normally block your view in a top-down perspective but would make sense for someone looking through the eyes of a marine to see and for light to bounce off of.

A lot of the new features concern marine bots and don’t even require mappers to do any extra work. For example, bots automatically detect the most frequently used method of creating elevators, trains, and other places where the team needs to gather in one spot, and will gather inside if the squad leader is there. Bots will also automatically gather inside level exits, drop healing beacons as medic and ammo from the ammo satchel, and flank shieldbugs when fighting them.

Alien Swarm’s birthday is a mere 15 days from now, on the 19th of July. It will be 5 years old. In these five years, over 800 years of Alien Swarm game time has been logged. More than 2,250,000 people have played the two missions required to get the TF2 hat. Here’s to another 5 years.

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v3 Full
Alien Swarm

v3 Full

Jun 18, 2015 Swarm Director 2 Full Version 1 comment

v3 is finally here, with a heap of bugfixes and new features.

Reactive Drop 1.17
Alien Swarm

Reactive Drop 1.17

Jun 18, 2015 Alien Swarm: Reactive Drop Full Version 4 comments

Delete old version. Extract to <path to steam>\SteamApps\sourcemods. Restart Steam. In this version you'll see bug fixes, map improvements, new map Nest...

Chaos Swarm Marines Red Edition
Alien Swarm

Chaos Swarm Marines Red Edition

May 29, 2015 Chaos Swarm Marines Full Version 0 comments

There new custom mod red edition special for chaos swarm marines and moddb, revision 7.3

Chaos Swarm Marines
Alien Swarm

Chaos Swarm Marines

May 29, 2015 Chaos Swarm Marines Full Version 0 comments

There new mod chaos swarm marines, revision 7.3

v2 Incremental Update 4
Alien Swarm

v2 Incremental Update 4

May 21, 2015 Swarm Director 2 Full Version 0 comments

An incremental update to v2 containing new features and bugfixes. Compatible with v2 through v2 Incremental Update 3.

Space Swarm Marines v8.1 (update)
Alien Swarm

Space Swarm Marines v8.1 (update)

May 20, 2015 Space Swarm Marines Patch 1 comment

Well done i fixed more models and animations. :)

Post comment Comments  (30 - 40 of 180)
█Black/Brunez█ Aug 10 2010, 9:28pm says:

While I´m waiting a better computer, I will take a look at it. This looks amazing! I can´t wait to have this!

(the Aliens really remember me the Zerg from SC)

+1 vote     reply to comment
Kyou. Aug 15 2010, 3:16am buried:


its not worth the download.

-13 votes     reply to comment
█Black/Brunez█ Feb 2 2012, 12:14pm replied:

I downloaded and liked.

+1 vote     reply to comment
catman_94 Aug 15 2010, 6:35am replied:

your not worth the effort trollin'

+6 votes     reply to comment
ʇɐuʞɐʇǝp Aug 15 2010, 11:05pm replied:

He's only kidding. I know him :P.

+4 votes     reply to comment
Papineau Aug 10 2010, 1:57pm says:

I feel sorry for Alien Breed.

+1 vote     reply to comment
Rny Sep 12 2010, 3:38pm replied:

You do realise that after Alien Swarm's release, more people bought Alien Breed?

+1 vote     reply to comment
Killer_man_1996 Aug 4 2010, 5:40pm says:

Maybe we always had Alien Breed but this is free! so Team17 now only have Worms...

That's a bit sad, but i like the idea of Valve

+1 vote     reply to comment
Knut Aug 4 2010, 3:52pm says:

just the best example for an indie game.
love valve for releasing it for free :)

+1 vote     reply to comment
ILOVEZOMBIESIDO Aug 3 2010, 3:22am says:

very good game. i have steam ut i onyly used it for talking but now that i have played this... its epic. great community and a even better game XD

+2 votes     reply to comment
noyart Jul 29 2010, 11:43am says:

Marins and aliens fromt the alien movies = epic, the feeling when you put up the sentrygun and see how the bullets just drop down from 200 to 0. UA-571C Sentry Gun <3

+2 votes     reply to comment
saivert Jul 29 2010, 5:40am says:

hmm.. if this is to be compared to UDK, then you would have to be able to make any kinds of games with the Alien Swarm SDK and not just mods for it.

so is this possible?

+2 votes     reply to comment
MrCrimson Aug 2 2010, 7:44pm replied:

No Alien swarm is not the UDK; alien swarm is a game UDK is an SDK much like, hey I don't know, the source SDK.

+2 votes     reply to comment
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Alien Swarm
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Released Jul 2010
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Highest Rated (4 agree) 10/10

for a free game, this is one incredibly fun sci-fi creation, building on steam's co-op capabilities, which gives it immersive replay value, making it an awesome return-back platform for general cooperative-skills practice with new gamers and relaxing eye-hand coordination training gamers usually seek. given its free access to the game's sdk, enriches the experience even further, adding various creative production of new game content based on valve's source engine. what would u need more from a top-down…

Jun 6 2011, 6:13am by goodone

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