Left 4 Dead series
Contents
Brief
The Left 4 Dead series[1] puts players in the roles of 4 characters trying to get to safety in a world where the majority of all people have been infected with a disease making them homicidal maniacs. Although similar to zombie movies as Dawn of the Dead or even more so infected movies such as 28 days later, it adds the concept of some infected being mutated to get various abilities. These mutants are simply referred to as special infected. Overall, the gameplay is similar to most first-person shooters but with heavy emphasis on co-operation and getting from one safe house to another.
The series currently consists of Left 4 Dead (L4D) and Left 4 Dead 2 (L4D2).
See wikipedia entries[2][3] for more detailed description of the games.
Main Gameplay Design Patterns
Aim & Shoot, Cooperation, Survive
Gameplay
Cooperation is a fundamental gameplay mechanism in the series, with players having the Mutual Goals for most types of game modes to Survive attacks by the infected while Traversing game levels in Real-Time through a First Person View. The exceptions are the Survival Mode which replaces the Traverse goal with a Time Limit goal and the Versus Mode when players having the role of special infected have the Preventing Goal of hindering those playing uninfected humans. The game levels are arranged into groups that define several different campaigns, giving the games Narrative Structure (in L4D2 these campaigns are also diegetically linked). All game modes except Survival Mode follow the campaign structures of the levels although the Versus Mode runs each game level twice before proceeding to the next level so that both teams can play both as humans and as special infected. Completing a campaign gives one of the Achievements in the games and there are additional Achievements for completing the campaigns at the most difficult level (and one additional one for completing it in Realism Mode for L4D2).
The players take the role of one of four Avatars which are diegetically different but have the same abilities within the game. The game always starts with all four Avatars in game, using Agents when not enough humans are playing. Through making it possible for people to temporarily give over control of their Avatars to Agents, the series shows that one can provide individual Game Pauses in Multiplayer Real-Time Games, although of course the overall gameplay continues. This, and the fact that players can log-in and take over Avatars that were controlled by Agents initially provides the game with Drop-In/Drop-Out possibilities.
The infected that passively wait for the characters, or come charging in hordes, are the Enemies in the game. These are mixed in with the rarer special infected (Hunters, Smokers, Boomers, Tanks, and Witches; L4D2 adds Jockeys, Chargers and Spitters) that function somewhat like Boss Monsters in that they are tougher opponents with special abilities but they are not only present at the end of levels or campaigns. L4D2 adds uncommon infected, one for each campaign with a minor unique ability such as being protected from fire (medical professionals in hazmat suits) or gunfire from the front (police in riot gear).
Like many First-Person Shooters each character as hit points to show how healthy they are. Beginning with 100 in health, the Avatars start having Decreased Abilities in the form of lower movement speed as they go below 40 in health and get progressively slower the more they are hurt. When health reaches zero one becomes incapacitated. In this penalized condition it is only possible to look in different directions and shoot with pistols while awaiting rescue from the other players; if all players are incapacitated the game level has to be restarted. Avatars can be incapacitated in others ways, either by falling of ledges or by being the victim of the attacks of the Hunter, Smoker, and Witch special infected (and Charger in L4D2), and in these cases also need other players to save them. Those incapacitated have Time Limits presented as decreasing meters (fatigue for those hanging from ledges and 300 incapacitated health otherwise, and die when they run out of time. Players that have been incapacitated three times in a row without being healed with medical equipment dies automatically, making the ability to become incapacitated a Limited Resource of sorts.
The games have Dedicated Game Facilitators in the form of AI Directors and Music Directors. The former measures how much problem the Avatars are having as an indirect indication of the players' Tension level to be able to vary intense gameplay periods with calmer ones and vary what special infected are encountered. The Music Directors are individual for each player and personalizes the music according to the health and context of player's Avatar.
The game levels are rather linear in structure, making the Traverse goal rather easy from a navigational point of view although L4D2 introduces some variety by randomizing between several different routes to provide changes in the level. This is further eased by the Avatars providing the players with directions as part of the discussions between themselves and that Outstanding Features such as lights form a Trace for the players to follow. Even so the game requires some Exploration since they need to find Pick-Ups in the form of weapons, ammunition and healing equipment and these do typically require some detours. Initially the Avatars only have a few types of weapons to use, limiting the efficiency of their Aim & Shoot actions especially since ammunition is Limited Resources for all weapons except pistols (the chain saw in L4D2 also has limited fuel). In L4D2 one starts with only melee weapons, probably to provide Smooth Learning Curves since they do not exist in L4D. Various firearms can be found later in the game as well as ammunition piles. All the healing equipment are single use Limited Resources. First-aid kits allow Avatars to heal themselves or others back to near full health while Pain Pills (and Adrenaline Shots from L4D2) function as Power-Ups since they only give temporary health benefits (performance benefits for the adrenaline shots). L4D2 adds the possibility of other players reviving dead Avatars if they have shock pads but people that have fallen out ledge are dead until the start of the next level. L4D2 adds tangible Shared Rewards through cases with laser sights or special ammunition (explosive or incendiary) that can be handed out to all players.
Some of the gamers actions in the games are both Extended and Interruptable Actions, specifically those that help the other players. Helping other players while they are hanging from heights or healing them takes time and can be interrupted by attacks (and is best done with yet other players having the Supporting Goals of protecting them). Besides providing Time Pressure these actions can also be seen as a form of Delayed Reciprocity since there is typically an unstated understanding that the helped players while in the future be helpees. Healing oneself with bandages is also an Extended and Interruptable Actions in the game, but since this also is best done when guarded by other players it also encourages team work.
Many of the design choices described above gear the overall gameplay towards encouraging Cooperation. The number of infected make it difficult to handle alone and typically they attack from many directions at once making solo exploration difficult. That players easily find themselves in dangerous situations they cannot get out of on their own as noted above regarding being incapacitated. The attacks by Hunters, Smokers and Witches (and Chargers in L4D2) are examples of this, but other special infected promote players to collaborate in other ways. The Tank is most efficiently fought by several players at once, victims of the Boomers' bile attack can with efficiency be defended by other players, and those ridden by Jockeys need to be freed by other players. The implied Delayed Reciprocity of
The series allow Betrayal in that players can opt to run to safe rooms or the escape vehicles while leaving the other players to their fate, choices that have persistent effects since only the survivors of a campaign get the Achievements associated with it.
Even players whose Avatars have been incapacitated can support other players since they can still shoot with pistols.
The games rely heavily on Achievements to provide Replayability of the levels and campaigns. Some of the Achievements are simply gained by completing the campaigns, others one can gain more or else through Grinding since they are based upon achieving a certain event (e.g. killing zombies with machine guns or honking the noses of infected clowns), and others through actions that require Timing or Game Mastery (e.g. throwing Molotov cocktails on a special type of zombie or killing Witches in a single shot), and yet others which make gameplay more difficult for the other players. The last category consists both of voluntarily limiting oneself to using less effective weapons and of goals such as carrying garden gnomes extensive distances (in L4D2. Although some of the Achievements can be seen as Optional Goals, these and the goals of completing levels and campaigns might effectively become Incompatible Goals.
Machine Guns and Mini Guns
Campaign Mode
Survival Mode
Added in an update of L4D but present from the release of L4D2, this mode gives the gamers a Survive goal where specific medals are achieved by being alive beyond specific Time Limits (4, 7, and 10 minutes for bronze, silver, and gold medals respectively).
Versus Mode
The Versus mode pits players against players with some playing humans and others playing special infected. This introduced Asymmetric Abilities on both team and player level. All special infected can see the
The special infected have
Single-Player Mode
Realism Mode
Added in L4D2, this mode removes all the glowing outlines (i.e. the Non-Diegetic Elements) around the PCs, weapons, and health equipment. The ammo dumps are an exception to this. By doing so the game both makes Exploration to find items (i.e. fulfill Gain Ownership goals) more difficult and increases the risk of friendly fire (i.e. makes Cooperation more difficult).
Other Noteworthy Aspects
Developer
Valve Corporation (Windows version) Certain Affinity (Xbox 360 version)
