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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v1 Full
Alien Swarm

v1 Full

Jul 4, 2014 Swarm Director 2 Full Version 0 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 0 comments

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 10 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 1 comment

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

Patch 1.07 to 1.08
Alien Swarm

Patch 1.07 to 1.08

May 23, 2014 Alien Swarm: Reactive Drop Patch 2 comments

Extract this into sourcemods. Requires version 1.07 installed

Post comment Comments  (50 - 60 of 184)
mufans Jul 22 2010, 11:22am says:

where can i download this? or is it just on the steam

+2 votes     reply to comment
Davkilla101 Nov 1 2010, 6:19pm replied:

@mufans steam is free, install it here (Top right button labeled "Install Steam")

+1 vote     reply to comment
skarai Jul 22 2010, 11:58am replied:

Think you need to download it from steam.

+3 votes     reply to comment
skarai Jul 22 2010, 4:03am says:

It's ok

+1 vote     reply to comment
Medevila Jul 24 2010, 2:27pm replied:

Well it's made to be modded- hence the one campaign.

+1 vote     reply to comment
BlindxLink Jul 21 2010, 9:15pm says:

This is a great game, and I hope to see people make some mods for it soon. If anyone ever needs help with their mod let me know. I'm a voice actor, and would love to help work with anyone that needs it!

+6 votes     reply to comment
Dremth Jul 21 2010, 10:05pm replied:

I'm thinking about making a mini-campaign, but it'll be a few weeks before I can even look into it.

+3 votes     reply to comment
BlindxLink Jul 21 2010, 10:23pm replied:

Yeah. I mainly mean if someone makes a mod with different monsters, zombies, or aliens. I could do the sound effects.

I could also be the "guy over the radio" that tell's the marines what to do if you need it.

This will all be way later on. Just letting you know. ;)

+1 vote     reply to comment
Dremth Jul 21 2010, 8:39pm says:

Ok, Alien Swarm. I've conquered your hard mode. A friend and I did a speed run through hard, just the two of us. Time to take a dip in the insane pool...

+2 votes     reply to comment
Boxiii Jul 21 2010, 8:57pm replied:

Insane is a whoooole other ballgame

+3 votes     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) 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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