“Highway 2 Hell” is a four-chapter Left For Dead campaign. It starts when the team crashes a car on the way out of the city. They wake up in a forest, find their way across a highway, through a tunnel, and manage to exit out of a tunnel access shaft. They exit and find themselves on a road that heads to the docks and follows it to escape the infected.”

Development Details

  • Program: Source SDK, Left For Dead

  • Development Time: 12 weeks, about 160 hours

  • Team Size: 4

  • Platform: PC



Gameplay Highlight 

This is the Gameplay Highlight for the Level





  • One half of the level should be wide with lots of landmarks and the other half should be in tight dark and claustrophobic spaces.

  • Provide multiple opportunities  for the director to spawn hordes.

  • The level should be densely packed and the aesthetics should be indistinguishable from the base game.



Left 4 Dead - Highway to Hell Perspective View

Left 4 Dead - Highway to Hell Perspective View

Left 4 Dead - Highway to Hell Perspective  View

Left 4 Dead - Highway to Hell Perspective View

Left 4 Dead - Highway to Hell- Upper Balcony

Left 4 Dead - Highway to Hell- Upper Balcony

Left 4 Dead - Highway to Hell- Cave Area

Left 4 Dead - Highway to Hell- Cave Area

Left 4 Dead - Highway to Hell Perspective View

Left 4 Dead - Highway to Hell Perspective View

Left 4 Dead - Highway to Hell- Tank Area

Left 4 Dead - Highway to Hell- Tank Area


Full Video Walkthrough

Here is a full video Walkthrough to summarise the entire campaign.



  • I applied what I learned during my DFS, carried over the knowledge and met and stuck to the milestone’s definitions and requirements.

  • The Campaign was a great success. Everyone did a great job, and the Campaign was in sync.

  • I made sure that I did not over-scope; on the contrary, I was under scope and added additional gameplay as needed to meet the requirements which was much better than cutting a lot of stuff.

  • I realized that rather than fighting with the director, I had to understand what it was good at and design my level accordingly.

  • This was the first time I used lights as an objective to pull the player towards them and it turned out as a pretty good technique that I ended up using it in others projects as well.

  • I met all of my initial goals, i.e., the level was designed so that the upper part of the flyover is well lit with lots of landmarks while the lower part is dark with many claustrophobic moments. I also provided plenty of opportunities for the director to spawn zombies. The aesthetics of the level was also pretty well done and was mostly indistinguishable from the base game according to certain playtesters.

  • This was also the first time I explored the audio side of level design, and adding those elements drastically improved the immersion of the level.

  • The level turned out quite a fun experience for most playtesters.

What went well

  • I had quite a lot of trouble with the navmesh initially as I was creating the nav in chunks rather than passes, which resulted in horrible AI path navigation, but that was later fixed.

  • My T-shaped level layout itself was bad as I had trouble creating proper vis_blocking portals. I managed to block some but this was something that I’d wish I’d had the foresight so that something like this could never happen.

  • There were many redundant brushes, while they were snapped to grid they were on the <8 grid, which resulted in me performing some horrible brush patchwork to fix the problem, and the latter led to the creation of unnecessary portals.

  • I did not have the opportunity to design strings of pearls in the level.

  • We had a lot of trouble initially to get the levels to sync on the transition between one level to another, and it took a lot of development time, but that was resolved in the end.

  • We didn’t end up assign responsibility for each other’s so at the ending safe rooms and the starting safe room that led to a lot of complications and patchwork to cover up those issues and even to this day some of the problems still lingers on.

What went wrong

  • Especially In source SDK technically everything is an interior space even the skybox should be airtight as if it is an interior space. If not, that creates additional portals and increases the build times exponentially.

  • In level design try to make everting as rectilinear as possible; especially the navmesh.

  • Nav cells should always be big and rectilinear.

  • I learned this quite late in the project and only could implement it partially but was super-duper helpful in the upcoming milestones; basically it was to create clip wrappers with an 8 or 16 px offset to any and all geometry they will have nav on top of it or needs additional detailing. By doing so the nav and the geometry is locked and the gameplay remains the same and we  can only focus on asthetics later on.

  • I learned the in’s and out of the Source SDK, and now I can confidently say I’m no longer afraid of it.

  • I learned actual level design as this project focused a lot more on the level design aspect of it.

  • I finally learned the reason for a grid and reinforced many fundamentals like snapping and building on grid, scale, size, proportions, and units.

  • Though late I gained some useful information of texture, textle density and why should we not scale models and textures.

  • I also learned that “Less is more”; Moderation is the key. The lesser you scope, the more things you can add and make the world more immersive

  • “It’s better to stand together than standing out”; One of the later feedbacks that I received was my level was standing out when compared to the others. Normally this would be good, but when working with a team it is vital to stay in sync and work on things where you don’t stand out, but the team standouts.

What did I learn