Zombie Panic! Source is a standalone cooperative, survival-horror, first-person-shooter! Set in the middle of a zombie apocalypse, players start as a small group of survivors attempting to stay alive. Each map will have its own objectives to complete and win the round or survive by a period of time.

RSS v3.1 Development Update - 10 Years on Steam!

We're back with another dev update to reveal more upcoming content, including a special day celebrating 10 Years of Zombie Panic! Source on Steam!

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We're back with another developer update to reveal more upcoming content from the unstable build, including a special day celebrating 10 Years of Zombie Panic! Source on Steam!

Mod's Backstory

Zombie Panic! Source was initially released on Dec 28, 2007 via ModDB page as a Half-Life 2's modification beta. Back then, you were required to own any Source game to play the mod. Valve then opened a new door for mods to be delivered through the Steam platform on Oct 3, 2008. Five of these mods, including ZPS, were selected to be integrated using Steamworks Distribution, which helps streamline the delivery, installation, and update process.

It also consists of features like Steam Achievements, Steam Workshop, anti-cheat technology, management of user-generated content, etc. Getting Steam'd was a huge step to deliver faster updates and get connected with our community even more. We're very thankful for Valve developing such a great tool for the gaming platform.

To celebrate this memorable day, we've gathered exciting news regarding v3.1's development that is ready to be shown to the public!

How things are looking

We're very glad to retrieve two old melee concept weapons from the grave: the Tennis Racket and a Broom! These will be available in the unstable build for public playtesting before v3.1 public release. We'll need your help in providing feedback and ideas to adjust them for being viable in melee combat in the future. If you're thinking that we will only add melee weapons from now on, well, don't lose hope! While we're not yet ready to show them off to the public, take heart in that we have some ranged weapons that we're working on.

Melee Showcase

We're also pleased to announce the official unveiling of the Biotec facelift! Casei has given the facility a more high-tech, corporate look while retaining the essential classic gameplay which you've come to know and love. There are brand new 3D props by both Darb Dudeand Ratboy, new particle effects by Dr.Vodker, new areas with better textures and decals, lighting improvements, and general bug fixes!

With these upgrades being made, we're aiming to distribute the same devotion to our other stock maps imploring for improvements and fixes. Asylum redux and Biotec editions are just the beginning of a much longer evaluation and update process. This is a long-term goal for the mapping team, but it's also a delicate process that needs careful attention to balance and detail, and we hope the results are as pleasing as Biotec's, as seen below:

Biotec 1

Biotec 2

Feed-O-Meter Adjustments

We've decided to make a couple of improvements to the Feed-O-Meter's usage and Berserk mode. The Feed-O-Meter will now auto regenerate itself when not in use. The regeneration process is very slow and you still should use your feed bar wisely. The Berzerk, on the other hand, now has its own bar separated from the normal Feed-O-Meter bar. This will make the zombie's life easier while allowing them to manage which feature they would like to use without affecting or wasting a single berzerk bar while lunging. The Berzerk function remains untouched beyond that.

Feed o Meter

This is a heavily experimental change that will require a long period of testing to assure it's well balanced and fair for both teams.

Zombie Teammates Glow

An additional zombie feature has also been added to improve the team's communication and create better tactical ambushes against the survivors. Zombies will be able to see their teammates glowing through nearby walls, but with a minimal range that is more limited when compared to the Carrier's roar glow - without consuming one Feed-O-Meter bar.

Upgraded Voice Menu

We've improved our voice wheel menu system, based on Left 4 Dead's radial menu, adding one extra survivor line: "Keep Moving!". This was unused content for a long time. All current VO's survivors had this line recorded and ready to use, but the previous team never went further with it.

Voice Menu

Sadly, due to the changes in the voice system, we were forced to change our voice menu's default keys, replacing with new code commands, which is why you will have to reset your client configurations in Game Options > Keyboard.

Server Browser Info Box

Finally, we've recreated our entire server browser window from the ground up, designing two different server tabs when searching for a community server. We also implemented one server information box advising newcomers about their first connection to any ZPS server. Hopefully, with this new info box, new players will be aware which type of content they can expect out of that server.

Server Info Box

Vanilla servers running pure ZPS gameplay will be displayed in the "Internet" tab, while custom servers running any modified plugins will be relocated to the "Custom Server" tab.

We've exhibited a lot more upcoming content (Linux client support, hitboxes fixed, weapon barricade adjustments, ammo hud changes) created to improve your ZPS experience in our previous article.

Build Status

We're very excited to get the core functionality of the build into the hands of the community as soon as possible to begin our first public beta playtesting with you all. While not everything will be properly balanced and working at first launch, the unstable build is well-considered "playable" at this moment. Hooray!

Meanwhile, we'll keep scheduling our internal playtesting and start organizing the preparations of our public playtesting. Feel free to join our official Discord server to not miss anything from us and lose the opportunity to opt-in the beta right away!

See you during Halloween!

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- Zombie Panic! Source Development Team


Maybe recommend updating the source engine you guys are using the tickrate for most games by default feels bad.

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Tabajara77 Author

Hi, if you have any tickrate recommendations, feel free to reach us!

Reply Good karma+3 votes

This is one of my all time favorite mods/games. A timeless classic. I think the only thing I would love to see is a rework of all the character and zombie animations. They look stiff these days. And I'd love a really nice limbloss/gibbing system to be implemented. Other then that the game still stands the test of time.

Reply Good karma Bad karma+6 votes

>Praise teamate

Teammate spells with two Ms, as it's comprised of team & mate, not tea & mate.

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Tabajara77 Author

Thanks for the heads up! I went unnoticed when we published. hehe

It's fixed now!

Reply Good karma+3 votes

Did you make it coop? Last time I played, not far from now, players were controlling zombies too.

Reply Good karma Bad karma+2 votes
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