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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About Swarm Director 2 with 2 comments by BenLubar on Jul 7th, 2014

If you play an Alien Swarm map, you see something like this:

In-game view of Area 9800 Landing Zone

If you're a mapper, you see something like this:

However, if you're an alien or a marine bot, you see something like this:

Node graph from Area 9800 Landing Zone

Today, I'll explain the third view. The one you don't see unless you're actually part of the game. The little yellow boxes (nodes) tell the AI "you can go here". The game automatically connects nearby nodes to form a node graph. It's like a street map, but there are no houses and streets can appear and disappear at any time if something blocks a path between nodes.

Hammer view of Area 9800 Landing Zone without propsHammer view of Area 9800 Landing Zone with props

On the left is a room with the props removed. On the right is the same picture, but with the props. Open them in tabs and flip back and forth a few times if you can't connect them in your head.

There are two main problems with this layout: there are no hints for marine bots and some of the nodes are inside obstacles. For example, the forklift, dumpster, crates, and shelves are on top of some of the nodes. Those nodes are effectively nonexistent because they're always blocked.

Hammer view of Area 9800 Landing Zone without propsHammer view of Area 9800 Landing Zone with props

In this picture, the marines have places to stand and the nodes aren't blocked by obstacles. Since the marines aren't allowed under the shelves or past the forklift, there are no positioning hints on the right. If there were, the marines could choose to stand there and try to walk where they can't. This is an example of a good layout for AI nodes.

In a game like Swarm Director 2 that depends heavily on AI, a good node graph is very important.

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Reactive Drop 1.10
Alien Swarm

Reactive Drop 1.10

Oct 8, 2014 Alien Swarm: Reactive Drop Full Version 0 comments

New weapons, bug fixes, map fixes, jump_jet_trigger for mappers etc. Extract to <path to steam>\SteamApps\sourcemods. Restart Steam

v1 Full
Alien Swarm

v1 Full

Jul 4, 2014 Swarm Director 2 Full Version 2 comments

The first release of Swarm Director 2! Adds navmesh support, several community campaigns, better marine AI, a more powerful AI director, and a new game...

Reactive Drop 1.09
Alien Swarm

Reactive Drop 1.09

Jun 21, 2014 Alien Swarm: Reactive Drop Full Version 1 comment

Full 1.09 version. Recommended for those who didn't have Reactive Drop installed. Extract to <path to steam>\SteamApps\sourcemods. Restart Steam

Patch 1.08 to 1.09
Alien Swarm

Patch 1.08 to 1.09

Jun 21, 2014 Alien Swarm: Reactive Drop Patch 0 comments

Extract this patch on top of 1.08 version. Added support for 7 bot marines. Added displaying of 7 marines in lobby screen.

Lambda Wars 2.3.6 FULL EXE
Alien Swarm

Lambda Wars 2.3.6 FULL EXE

Jun 9, 2014 Lambda Wars Full Version 14 comments

Install Instructions: 1. Run the Installer and follow the instructions. 2. Restart steam. 3. "Lambda Wars" should now appear in your games list. If you...

Lambda Wars 2.3.6 FULL 7z
Alien Swarm

Lambda Wars 2.3.6 FULL 7z

Jun 9, 2014 Lambda Wars Full Version 2 comments

Install Instructions: 1. Extract contents into your sourcemods folder (default location: C:\Program Files (x86)\steam\steamapps\sourcemods). 2. Restart...

Post comment Comments  (70 - 80 of 184)
badMEDIA Jul 20 2010, 8:25pm says:

anyone know how to use an analog as the mouse in this game?
I'm using my PS3 controller, everything works except even
if I assign the mouse to my analog, A.S seems to overide it
and only allows the mouse :(

+1 vote     reply to comment
TensaZangetsu Jul 20 2010, 11:01pm replied:

did u try unplugging mouse while u have it in and can u tell me how u use ur ps3 controller cuz i wnna use mines

+1 vote     reply to comment
rorios Jul 21 2010, 12:32pm replied:

Just a question, but has anyone got this working with a controller? an if so, whats the gameplay like suing a controlling instead of a mouse of keyboard?????

+1 vote     reply to comment
rorios Jul 21 2010, 12:34pm replied:

balls I didn't mean for that to be a reply comment

+1 vote     reply to comment
Jhaxavier Jul 20 2010, 8:15pm says:

My God, this game is amazing.

+1 vote     reply to comment
operation_turkey Jul 20 2010, 7:55pm says:

Does anyone know if the difficulty sclaes correctly with the number of players? I was playing the campaign with my brother and we where forced into playing medic/technician in order to have sufficient utility, but we lacked having a balanced squad since AI players do not join, making the game very difficult even on normal.

+1 vote     reply to comment
ᎶʋƝʂℋɨƤ_ℳƘ_ƖƖ Jul 20 2010, 3:33pm says:

epic bug hunt is epic!

my mark is 10/10

Epic battles
Cool story
Good bug designs ( original )
Epic coop play
Epic map design
Awesome bug sound
Epic All sounds
Cool Unlockables
New awesome source engine

Now we need more campagins :)

+4 votes     reply to comment
RockerFox Jul 20 2010, 8:03pm replied:

also don't forget the most important thing, its free...and it has a flamethrower

+1 vote     reply to comment
Curse231 Jul 20 2010, 1:43pm says:

i hope there will be more caimpaings

+4 votes     reply to comment
rorios Jul 21 2010, 12:42pm replied:

Not really sure how you can list whiny kids saying it's a free game so it shouldn't deserve proper feedback. If anything I would expect the whiny kids to be the ones who would want to complain about stuff they don't like in a free game. So to be honest, I'll stick with, if you don't want it, don't download it, simple as that. also, thats not really a con of the game, thats just pointing out something you hate about the community, so therefore shouldn't really be on the list. I agree constructive criticism is fair enough.

I actually love this game, it's just too bad the campaign is so short. although, I can imagine people are already working on custom campaigns for it, much like left 4 dead.

+1 vote     reply to comment
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Alien Swarm
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Released Jul 18, 2010
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Highest Rated (4 agree) 9/10

The fact that this game is free continues to amaze me. Alien Swarm is a top down shooter that feels like futuristic Diablo II to a large degree. You fight off hordes of aliens with your friends in order to complete missions that require teamwork skill, and sometimes a little luck. The game has RPG elements – you level up and get access to new gear, there are four character classes, and multiple characters within those classes to select. This game should be a popular addition to any LAN party or…

Aug 29 2011, 12:04am by Rodman49

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