Alien Swarm: Reactive Drop – Official Infection Mode Guide

Infection is a Deathmatch Challenge/Game Mode that officially became a part of the game (This means you can play Infection on any server).

Guide to the Infection Mode

All credit goes to ModdedMarionette!

The Human Team wins by surviving against the zombies until the time ends, the Zombie Team wins by infecting all humans before the time ends.

How to Enable This Game Mode

The lobby needs to first have an active Deathmatch game running.

Next, the Lobby Leader needs to open the map tab and activate Infection via Challenges.

The game begins immediately when there are at least two players ready.

The script will try to automatically switch the ruleset to Team Deathmatch, but if it takes too long to do so on its own, try to do so manually as this game mode requires Team Deathmatch to be running.

The Humans

The Human Team wins by surviving against the zombies until the time ends.

Health

The humans have access to a health pool that is 10 times what their marines normally have.

Although, this does not mean too much to the humans as their deaths from zombies are usually the results of instant infection (or occasionally insta-kills from zombies’ physical melee damage if they do manage to score a hit).

It is like this so humans are not as fragile against damage sources other than zombies’ infection and melee damage.

Marine Stats

Marine stats still make a great impact on the gameplay. For example, the most apparent impact is health, as the bonuses come from the marine stats can be hundreds of health point differences.

The only exception is the speed bonus, as all marines have the same speed as Wildcat in this game mode, making Wildcat’s speed bonus an invalid incentive for picking her over others.

Another exception is all of Medics’ Medic-exclusive skills, as currently healing weapons are locked from usage. This means there are not really any real incentives for picking Medics over other classes. This is, however, planned to be changed.

Last Stand Mode

When the lobby has more than 4 active players, the last humans standing have access to Last Stand mode.

This mode can be activated via the melee key when the prompt shows up.

In this mode, humans will lose all of their weapons (but not their offhand equipment) and will only have a chainsaw to use. Meanwhile, humans in this mode are immune to infection.

Furthermore, humans that activate Last Stand will gain an amount of bonus maximum health that scales with the number of existing zombies in the match (marines’ health bonus skill still makes an impact here), meaning the more zombies you are versing, the tankier you become.

The Chainsaws

The chainsaw has much greater damage in this game mode, with enough DPS to kill any zombie in split seconds (but not enough to one-hit full health zombies). Although this isn’t a stat exclusive to the Last Stand mode, it is much safer to make use of this in the Last Stand mode since humans are immune to infection in Last Stand mode.

The Zombies

The Zombie Team wins by infecting all humans before time ends.

Health

The zombies have access to a health pool that is 20 times what their marines normally have.

This means Sarge, with a base hp of 140, would have a maximum health of 2800, compared to, for example, Wildcat’s 1600.

Prime Zombies, on the other hand, have a max hp of 40 times their base hp instead of 20. Wildcat, for example, would have 3200 max hp as a Prime Zombie.

Attacks

The zombies can attack humans in three methods:

One, the zombies can use the chainsaws attached to their limbs to damage humans to immediately infect them, turning them into a zombie as well.

Two, the zombies can also use physical melee attacks that do damage instead of infection. Humans without Last Stand activated will be insta-killed by this attack. This is difficult to pull off but can be an alternative option in certain situations.

Three, the zombies also have access to special hand grenades that regenerate over time. These grenades can create knockbacks, making them tools for disrupting the footholds of humans rather than killing as their damage isn’t enough to kill humans effectively.

Prime Zombies

Prime Zombies are stronger zombies that not only have access to an even larger health pool than a normal zombie, but also a shield that regenerates very shortly after the zombie stops taking damage.

Prime Zombies’ shield has a health pool of 10% of their own health. This means Wildcat’s shield, for example, would have 320 max hp.

Furthermore, Prime Zombies’ grenades also regenerate faster than normal zombies.

When a round begins, a random player (or two if the lobby is large enough) will become Prime Zombies for the rest of the round. They are the source of the infection and this is the only way for them to spawn.

Grenade Jump

The zombies’ special hand grenades can not only launch humans, but also the thrower of the grenades themselves (cannot launch fellow zombies), making them an effective tool for grenade-jumping.

Modified Maps

The following maps have access to exclusive edits from this game mode:

• DM Desert
• DM Deima Surface Bridge

Scoring

Score points have zero impact on the gameplay. This is just here for anyone interested in how it works:

• A kill gains you a point as they always do.
• An infection gains the zombie a point.
• Humans that survived a round will gain a number of points that depends on the number of existing zombies.