Introduction

Turtle Rock Studios are best known as the team that were in charge of developing a number of Counter-Strike products working with Valve, including Counter-Strike for the Xbox, Counter-Strike: Condition Zero and Counter-Strike: Source. Now Turtle Rock are striking out on their own with Left 4 Dead, a Source engine zombie action game that will concentrate on co-op multiplayer. Turtle Rock founder Michael Booth recently answered some of our questions about Left 4 Dead which is due for release on the PC sometime later this year.

FiringSquad: First, how did the idea for Left 4 Dead come about?

Michael Booth: During the past few years while collaborating with Valve on Counter-Strike and the CS Bot, we've been experimenting and iterating with co-op game designs, all of which have gravitated toward the survival horror theme. Left 4 Dead represents a growing collection of the best features and ideas we've come up with during this iterative design process.

FiringSquad: Why zombies as the main enemy instead of things like aliens or monsters or counter-terrorists?

Michael Booth: The concept of being surrounded by hordes of rabid, dangerous creatures is a natural reinforcement for co-operative play. I also find the idea of a horrific civilization-disrupting pandemic frighteningly plausible, which adds to the drama and atmosphere. Plus, it's fun to shoot zombies.

FiringSquad: What can you tell us about the main human characters in the game and how different they are in terms of gameplay?

Michael Booth: In Left 4 Dead, players may assume the role of any of the four Survivors or one of four "Boss Infected." Our AI technology allows games of 1 to 8 players - bots will assume the remaining Survivor and Boss Infected roles when human players are not available. The four Survivors have the same abilities and weapons available to them at the beginning of each campaign. However, it's the weapons you find and the tactical choices you make that define your role on the Survivor team.

FiringSquad: You can also play as zombies (or as you call them "infected"). What can you tell us about the different types of zombies in Left 4 Dead?

Michael Booth: First, there are mobs of AI-controlled Infected raging just about everywhere. Then there are five "Boss Infected" (Witch, Boomer, Hunter, Smoker, Tank) - four of which may be played by human players (all but the Witch). The Boss Infected have suffered unique mutations that can be leveraged in interesting ways by the player. The Boomer, for example, is filled with methane gas and can blast nearby Survivors if shot in close quarters, causing him to explode like a bomb. Alternatively, he can empty his gullet by projectile vomiting onto an individual Survivor. This vomit attracts a horde of common infected to attack whoever is coated by it.

FiringSquad: What will the environments and locations be like in the initial release?

Michael Booth: Left 4 Dead takes place in modern settings where a new and highly virulent strain of the Rabies virus spreads through the human population. Through the course of their missions, Survivors traverse urban and rural areas, and obtain weapons you would find -- and perhaps create (Molotov) -- in today's world.

FiringSquad: What are the main goals in each round of the game? Is it just to stay alive as a human or destroy humans as one of the infected or are there other goals as well?

Michael Booth: Similar to Counter-Strike, the goal of the environments and objectives are designed to present immediately recognizable situations that also allow for unique combat, even when played multiple times. In this case, each of the four campaigns included in the first release are of the "Escape and Survive" variety for the Survivor team. However, each mission is set in different geographic places which naturally lend themselves to varied play styles and challenges.