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.

Add mod Mods  (0 - 30 of 43)
Alien Frenzy

Alien Frenzy

Real Time Strategy

The year is 2026. The earth has been mostly destroyed by sunflares after the alien invasion. It seems their planet was destroyed first. The aliens came...

Alien Haunt

Alien Haunt

Adventure

Alien Haunt. A Map for Alien Swarm. 1 Campaign with 5 maps. Get ready to be swarmed by aliens!

Alien Swarm Aliens Mod

Alien Swarm Aliens Mod

Tactical Shooter

this "mod" will replace weapon's data and sounds for alien swarm making it feel like Aliens. Furthermore, maps will be made for this mod and the final...

Alien Swarm Director Mod

Alien Swarm Director Mod

Third Person Shooter

Welcome to the Alien Swarm Director Mod! ASDM is a single player Alien Swarm mod focusing on increasing replayability by creating a dynamic experience...

ALIEN SWARM FP

ALIEN SWARM FP

First Person Shooter

This is a first person view modification of "Alien Swarm"

Alien Swarm SDK Template Conversion

Alien Swarm SDK Template Conversion

First Person Shooter

C_b_fofep and I decided to convert the Alien Swarm build back into an FPS source engine version. This takes the orange box or the SDK template code and...

Alien Swarm: Reactive Drop

Alien Swarm: Reactive Drop

Arcade

Adds new PvP game modes, co-op features and singleplayer support into Alien Swarm without changing its concept.

Alien Swarm: Rifle Mod

Alien Swarm: Rifle Mod

Arcade

Rifle Mod is an Alien Swarm server-only mod that forces players to play with assault rifles only, harder aliens, more ammo, smarter bots. However rifle...

Alien Swarm: The Darkness

Alien Swarm: The Darkness

Tactical Shooter

The Darkness is a mod designed to put the players into a much more difficult position than that of the original Alien Swarm, by removing a lot of lighting...

Alien Swarm:Silencer Mod

Alien Swarm:Silencer Mod

Third Person Shooter

Do you think the aliens are deaf?Unfortunately,they have perfect hearing ability.In another word,the huge noice comes from your weapons can attract the...

Alien Swarm:SP

Alien Swarm:SP

Third Person Shooter

Play the official Alien Swarm maps and any addons through the Offline Practice mode. Alien Swarm:SP also supports a large amount of configurable changes...

ALIENS

ALIENS

Tactical Shooter

A mod for Alien Swarm that is based on the ALIENS movie but for a set of new marines to go and investigate LV426 and see what happened there! (This is...

Apocalypse-22

Apocalypse-22

First Person Shooter

Apocalypse cuenta la historia de Abigaíl, una mujer de 28 años de edad en un futuro apocalíptico y sin memorias de su pasado. (Historia en desarrollo)

ASB²  mod

ASB² mod

Tactical Shooter

ASB² mode (alien swarm beyond brutal) is a reborn ASBi game mode emphasizing the higher degree of difficulty, which includes the invalidity of such options...

B.R.I.S.k.

B.R.I.S.k.

Arcade

B.R.I.S.k. is a game with unique gameplay developed by a team «Two On The One Box», which has created a modification for the game Portal 2 - Afterword...

Black Mesa Swarm

Black Mesa Swarm

First Person Shooter

Black Mesa Swarm is an Alien Swarm total conversion remaking Valve Software's award-winning PC game, Half-Life.

Brawlers

Brawlers

Third Person Shooter

After the dust had settled from the worlds greatest war, stockpiles of defunct weapons and ammunitions around Europe were scheduled for destruction. Private...

Chaos Swarm Marines

Chaos Swarm Marines

Third Person Shooter

There new mod for Alien Swarm, so on release we have new models and custom particles. More new portraits and other changes.

Enhanced Interstella Armed Forces

Enhanced Interstella Armed Forces

Third Person Shooter

A new MOD based on Alien Swarm 2011 version. It is an independent game that does not need a installed Alien Swarm. Many data about marines and equipments...

Hypovolemia

Hypovolemia

Third Person Shooter

HYP is real time tactical shooter with chess like awareness and high skill ceiling. The game focuses on intricate game design while offering a unique...

IAF Weapon Drop

IAF Weapon Drop

Third Person Shooter

Almost all weapons were modified more or less noticeable. Some of them are big changes (like semi-auto Railguns and Sniper Rifles or Miniguns with lot...

Infestation

Infestation

Third Person Shooter

Lots more details in latest news post, looking for more team members too - if you feel you have something you could add to the mod send me a pm for a...

Infested Office

Infested Office

Third Person Shooter

A test of skill and teamwork, this addon/map pack challenges you and your team even on the easier difficulty settings.

Lambda Wars

Lambda Wars

Real Time Strategy

Lambda Wars (formerly Half-Life 2: Wars) brings the struggle between the human resistance and their Combine overlords to a multiplayer real-time strategy...

Lights

Lights

Cinematic

Once you find the light, nothing can defeat you...

Lylat's Last Stand

Lylat's Last Stand

Third Person Shooter

SFR (WIP title) is a mod for the Source Engine. It's based on the 3d shooter game Starfox. It will be mostly based on the 1993 nintendo power comics...

Marine retexture

Marine retexture

Third Person Shooter

this addon makes the marines look more dirty & the sarge has a camo now,

Modular Combat 2

Modular Combat 2

First Person Shooter

Modular Combat 2 is an upcoming role-playing shooter based in the Half-Life universe. The game will feature upgraded graphics with custom shaders, AI...

Omnibus

Omnibus

Arcade

Warhammer 40k mod for Alien Swarm. You play as one of four members in a Space Marine squad and you're sent to a Tyranid infected planet to investigate

Optic

Optic

First Person Shooter

Optic is a team-based multiplayer shooter where players can take the role of either a fast-moving runner or a slow-moving hunter.