A Theory on Infection Mapmaking

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A bit of a background before beginning:

I wrote this guide as a means of changing conceptions behind building infection maps, and thus resulting in better, less-criticized creations in the future as I love Infection and hope it grows as a gametype.

Here are the topics covered.

1. [jumpto=a]Balance[/jumpto]
2. [jumpto=2]Last Man Standing[/jumpto]
3. [jumpto=3]Alpha Zombie[/jumpto]
4. [jumpto=4]Weapons[/jumpto]
5. [jumpto=5]Team Play[/jumpto]
6. [jumpto=6]Atmosphere[/jumpto]
7. [jumpto=7]Power-Ups[/jumpto]
8. [jumpto=8]Switches, Events, and Teleporters[/jumpto]
9. [jumpto=9]Basic Types of Maps[/jumpto]

I have a lot of experience playing multiplayer zombie games. It started with 16-man LAN parties for Halo 2 where we played infection for hours on end and due to the monotony of the maps, it required cleverness and quick reflexes to stay alive or murder the opposition. However, those events were few and far between and I soon caught wind of the highly customizable Counter Strike: Source, which was a physics upgrade to my school-time love CS. After about a day of playing I discovered a zombie-mod server and my six-month binge began.

Most of the maps were superbly-made and well-balanced. Furthermore, camp spots either required immense skill to reach as a human or amazing barricade-building abilities (using your bullets to propel all manner of object towards the open door) and no matter what, the zombies got through. Whether you were skilled enough to hold off their assault until the round ended is an entirely different matter.

In order to survive as either or a zombie or a human, you needed to be intelligent and have a vast array of problem solving abilities.

The Good Stuff

Now Halo infection as I've experienced it (aside from mini-games, its all I ever play now) is much more simplified.

Sure, that may just be the “Fat Kid” variant or any of it's derivatives, but the fact remains, most Infection maps suffer from a lack of complexity.

Now, I'm not saying that these types of maps should be built with crazy corridors and dynamic environments, but there needs to be something that keeps everything in equilibrium, which brings me to my first point.


[aname=a]Balance is key, you see.[/aname]

It all comes down to a few graphs.

The common misconception is that infection outbreaks (that is, zombies killing humans) should occur in bursts on certain segments of the map, oftentimes this occurs close to the start of the match, in some choke-point designed to doom a few laggers and boost the zombie count, thus foregoing common sense by ignoring the “initial zombie count” option in the gametype settings. These bottlenecks create chaotic gameplay and can typically be illustrated analytically by a positively skewed graph as shown below.

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The bulge in the line shows the common zombie kill upsurge that occurs somewhere early on in the game. As the round progresses, a funny thing happens, humans are harder to kill and die far less often. Whether this is due to traits, custom power-ups or the map layout itself is variable.

Common sense would dictate the opposing trend to occur, as time goes on, infected kills should accelerate as more zombies overwhelm the human populace, then drop off slightly, thus resulting in a steep negatively skewed distribution of death. However, this mindset tends to overwhelm us and maps are designed accordingly, making it harder for humans to progress. As such, the perfect Infection graph tends to shift from a nice data hill of doom on the right

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to an exponential curve that slants upwards.

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Humans stand no chance towards the end, they are literally awaiting their fate, all suspense [jumpto=6](covered later)[/jumpto] is defunct as every match ends the same way. Zombies: Innumerable. Humans: Zip.

When building the map, you must always keep balance in mind: if odds are stacked in the humans' favor, add a secondary route for the infected, if there are too many zombies, add better weapons, close off a few paths, do something. The last human should never feel like they're going to lose. There should be an ever-looming sense of death, sure, but don't make playing seem trivial. If the map ever succumbs to a loss of hope, it becomes monotonous and the human may as well not waste their time.


[aname=2]Last Man Standing and other clichés[/aname]

Now, going back to the idea that humans usually become overpowered as the game progresses to compensate for the growing opposition, by extension the “last man standing” tends to fall under this mantra as well.

Generally speaking, the final man has help in order to give him a fighting chance, however, many mapmakers tend to replace “aid” with “mercy” and give the last hope for humanity a multitude of weapons [jumpto=4](covered later)[/jumpto], better traits, or safe spots to rack up kills and wait out the round. This not only degrades the experience by becoming boring, but also leads to frustration for the players who desperately attempt to kill him. Personally speaking, I'd rather battle a better opponent and lose consistently than fight a foe who has an unfair advantage and end with the same result. The best way to circumvent the common mistake is to simply (and once again) adhere to common sense.

If the zombies actually took over the world, and a final man emerged, lamenting the loss of his kind, would he be all the stronger for it? Philosophy aside, the answer is "mostly no." Technically speaking, in harsh situations, one's sympathetic nervous system releases adrenaline, resulting in a burst of energy, speed and strength. Realistically, this surge only increases those facets minimally above normal. Now, think back to that when designing Last Man traits.

Should the Last Man suddenly become incredibly fast or incredibly strong?
Should he possess the magical ability to instantly kill anything?
Should he have a miraculous amount of weaponry available to him once he reaches a certain point?
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Sure that last comment isn't a trait, but the answer remains the same: no. Always remember, keep hope high in players on both teams to keep your game thoroughly interesting and engaging, one side should not overpower the other. The end of the game is as crucial as the beginning, and so the zombie traits should be discussed as well.


[aname=3]Alpha Zombie and their Lackeys[/aname]

In my experience, games with Alpha Zombie traits that differ from the normal infected tend to have very disorganized gameplay. The starting zombie will have have their traits made specifically to serve as a bottleneck for the beginning of the game, killing many players right off the bat, or in vehicular gametypes (DO NOT USE VEHICLES) they are the only ones equipped with a plasma pistol, but the rest of the game they're useless or overpowered. Not only is this shoddy gameplay, its really boring and kills replayability.

Start Alpha Zombies with the same traits you are going to give the rest of the infected, then slightly change them to your liking, but only if absolutely necessary to your game, otherwise leave them be. After all, why would one zombie have the advantage over the others?

As for the zombie traits themselves, it truly depends on the style of map you are trying to achieve. If your map is of the camping nature, the infected should be quicker than humans to counterbalance the lack of movement for the living. If your map relies on player movement, humans should have weapons that can keep the infected at bay (if they're significantly faster) such as an SMG as they move through the map.


[aname=4]Armories and Ammunition[/aname]

Consider the following:

• The Zombocalypse has just occurred.

That's it really, most authors have that in mind when making a traditional infection map. Said maps feature zombies hunting humans with close-range weapons, thereby imitating popular culture in which they could only attack with their bodies.

Now suppose said circumstance is real, unless you're part of an elite squadron of soldiers for the government or some paranoid hermit waiting for his day, chances are, you wouldn't be adequately prepared. Think in that very mindset when designing how a game on your map is meant to play out.

Humans should have the bare essentials, normal traits (in relation to the zombies) and adequate, if not lacking, ammunition. DO NOT GIVE UNLIMITED AMMO, it is no longer infection at that point, it is a casual excuse for a zombie game (not inferring it is inferior, but you're setting out to create something that this guide isn't meant to help with). Returning to the point about hope, zombies should never fall into boredom as a result of the overwhelming power of the humans, as such, their opponent's firepower should be just enough to keep one relatively safe, but not invulnerable, so lay off the rockets, br's or any form of all-purpose, omnipotent weapon.

Furthering the realist's perspective, armories should be few in number, if not nonexistent. Now, many infection "gurus" will claim that there should NEVER be an armory on your map whatsoever, I disagree. I believe that an armory on your map is not only possible, but can be influential in driving player motivation if used in the right circumstances.

Do not take what I just said and claim it free reign to place an armory or two on your infection map, as I used "can" in the qualifying sense, its a possibility, not a requirement. However, there are requirements your map should meet before placing a weapon cache down.

1. Is it realistic for there to be an armory?

Really, is it? Would you honestly see a multitude of weapons strewn about on a city floor with full ammunition? Would you really see them in the midst of a catastrophe when they would be extremely useful? Doubt it. Now, realistically, you would need to visit a gun shop or a military base to access that many guns, unless of course you're a hermit who's been awaiting the apocalypse for quite some time. But of course, if that were the case, you wouldn't be running about in the open with many other people, which is what Halo Infection is based around.

With that in mind, the logical alternative to open weapon placement would be to place them in some challenging location on your map, as that would simultaneously drive players forward and balance the gameplay, since the way would undoubtedly be fraught with misfortune and danger.

In essence, keep the armory (multiple ones, unless extremely small and even harder to access, tend to sway the game in the humans' favor) somewhere in the middle of the map. Also, they should be extremely dangerous places to access. Simple risk vs. reward. You need to have the incentive to get there, but there need to be qualities in the journey that counteract that notion, so that it is a decision to get there, not a force push in that direction [jumpto=9](covered later)[/jumpto].

This doesn't mean that the armory itself needs to be off the beaten path, way off to the side (though that is a suitable, if not favorable, alternative), it can be directly in the normal gameplay path of the humans, but there should be a higher element of danger in such cases, to account for the lack of the wayward journey you'd employ otherwise. Such danger points could be explosives (if the infected use weapons), switches [jumpto=8](covered later)[/jumpto] that the zombies can access, or just more openings in that area for the humans to be attacked.

2. Would it sway the game?

Just because this is number two, it doesn't imply this idea is inferior to the previous point, they are equal in merit, baby steps, balance [jumpto=a](covered earlier)[/jumpto]. Would the journey be worth the ammunition? If your players are equipped with SMGs, the chances are they'll be low on ammunition much of the time, an armory is probably welcome. Don't use the armory as an excuse to introduce new weapons. They may be included, but there should be significant ammo for the starting weapons there as well, after all, you gave them the weapon for a reason, stick with the initial decision, constantly shifting the weapons around not only disorients the player (to a degree, since weapons have different effects) but it can lead to shoddy gameplay if you need to focus on different aspects of the map. This should be one coherent experience [jumpto=6](covered later)[/jumpto], not multiple, disjointed sections calling for different gameplay.

Furthermore, you need to account for the later gameplay, especially if new weapons are introduced. Would they imbalance the game at all? Would being forced to switch from quick-fire SMGs to a single pistol per person really be fair? Rhetorical question, the answer is no. You should limit new weapons to those that are similar to your initial choice (that is, quick fire, weak weapons should be exchanged for other quick-fire, weak weapons) or if drastically different (one Shotgun in an SMG-based game), to one person.

Not only does this follow the "climax" ideal that once you reach that point, the action doesn't let up, but it makes the journey for the humans more enticing, and the zombies have a reason to mercilessly kill the opposition.


[aname=5]Live Together, Die Alone, Repeat.[/aname]

Back to the realism motif. Now, humans are social beings, studies have shown that those stuck exposed to high levels of stress will prefer groups over isolation (Shachter experiment). With that in mind, your game should revolve around the team mechanic, players working together to overcome the improbable and survive, as the closer to realism, the more the player can identify with the situation, thus leading to more tension and suspense, two adjectives you want to acquaint yourself with.

Keeping players together isn't as challenging as it sounds, people tend to play as a team unit, especially when confronted with threat such an opposition filled with fortunate and skilled players. The problem actually lies with keeping the [title=courageous]idiotic[/title] players from straying away from the group, you'll find that once one person is slaughtered or quickly disposed of as a result of their actions, the rest of the group falls in line, at least for the time being. Sure, this seems awfully authoritarian, but this is your game, make the game revolve around what you want, and receive your cult of personality's praise.

The main method is to keep such unfortunate (but inevitable) situations is to increase the difficulty tenfold when someone is alone. There are numerous ways to do this and it really depends on your gametype. If the zombies require a full clip of ammo to be put down (and that may be drastic considering you will be limiting their ammunition) then soloing an area is definitely going to rough once the infected catch the scent. That specific example is extreme, since you should not make zombies that hard to kill (unless you've some sort of compensation for the humans, like, and please don't do this, the zombie is some extremely slow miscreant) but you should think in those terms, making it balanced from a team perspective, but difficult if it isn't kept in play.

You may be thinking that this contradicts my earlier statement about hope being necessary for the game to be fun, and you would be half-right. Your map should be designed to have the humans slowly getting killed off and the team is forced to shrink as a result, thus balance would slowly shift in favor of the zombies, but the entire journey to that point should punish humans ignoring the team mechanic (made for the game to be balanced) and going lone wolf.


[aname=6]At Most; Fear.[/aname]

Atmosphere, something mapmakers tend to take for granted. Let's assume you're watching an amazing horror movie (if only, I've searched long and far in vain, but that is beside the point), the key principle to getting a scare out of you is atmosphere. Sure, there are key moments designed to get you all jumpy, but the resonance behind a clever scary film, the lingering feeling you get after watching it, is the atmosphere, the feel of the film.

When it comes to gaming, my favorites have been those where I felt I was a part of the world (Bioshock, Fallout 3, Morrowind, etc), it felt like, if I wasn't there watching, the events would proceed without me. Now, a map certainly won't reach that level of immersion since we lack the tools to do so, but impossibility doesn't discount effort, get that A! In infection games, you need to provide some concrete world, as you are essentially telling the story of the end of the world, what gets more epic than that? Most infection authors merely disregard this, assume infection itself is just a mechanic and not a means for storytelling, and that's when terrible creations emerge. If you truly want to get the player involved, get them paranoid about every corner, ever crack in the ceiling, you need to put them in a dangerous environment and never let up.

Some people create amazing environments full of aesthetic touches and events meant to convey that you're in a dying world ready to take its last breath. That is awesome, go for it if you're inclined to do so, more power to you. However, its unnecessary, its a trivial step (in terms of gameplay) and it only betters what you have, but doesn't actually create something memorable for players. The main factor is how you convey the danger in your map.

Now, to get your players paranoid, you need to have specific areas in mind where the infected will attack the humans. You can plan to build the map as you go and just insert choke points here and there (which I don't advise, as they break the death-flow, see balance) but that is just lazy mapmaking. I'm not saying you should plan every facet of your creation ahead of time (I certainly don't) but you should have a general idea of what will happen and where it will occur. A general example would be including specific areas where there are multiple entrances for the zombies (whether that be below, above, etc) if your map follows a linear playstyle. Close corridors and corners are also a good idea, as they cut line-of-sight (just as important in an infection map as any other) and keep people in a tight group. I can't list all the options, but I think the ideas been conveyed.


[aname=7]Orbs of Power[/aname]

Kalimah! KALIMAH! KALIMAAAH! In case you didn't catch the reference, some mapmakers literally deify the power-ups, okay maybe they don't worship them, but they tend to build altar-esque structures around these game-changing items, which is fine in most maps, but never in the glorious game of death that is Russian rou-infection. I do love me some roulette though.

As I was saying, Active Camos (hence bastardized as "invisibility") and Overshields are trivial objects to put in the game, as they literally "change" the game rules for a specific player for set traits. I realize you can change specific properties for it, but really, you should just stay away from them, people tend to get caught up on using them and as such add another facet to focus on and counterbalance in the game. For example, if you're in a standard game, a human picks up the power-up and suddenly can outmaneuver or overpower the infected. So the humans get the advantage for a while, which would be fine if you could balance against that, but there are no counter-overshields.

Anywho, some of you still may not be convinced, as you probably want to make switches or just unbalance the game because that's how you roll yo. Well, the fact of the matter is, you have two alternatives.

1. Set Traits

Rather obvious, but you can tweak the gametype to fit your fancy before actually playing on the map. Some people like to do this prior to building the map itself, which is fine, planning is always effective, but you should not get caught up in the details, since the map should not be built around the gametype.

I realize some people don't follow this as they'll build for someone else's fun gametype. That's fine, do what works for you, but if you're starting from scratch, forging for a gametype that hasn't proven effective and successful, its just in your head "this is how I think its going to play out", then you should just stay on an idea, build your map, and refine the gametype itself after completion.

2. CUSTOM Power-ups

These objects are great for various reasons, the reason is implied in the first part of their name; customization.

These magnificent, sparkling little gems can be used as direction markers for open world maps or to help stupidity along in linear ones. Sure, you can use the invis or overshield for it, but in those cases it is unwise to place the item in the middle of a reachable player path. With custom power-ups you can use subtlety and mark the correct direction by literally placing them in strategic areas or as a useful tool for player incentive. Why? Because you can set them to have no effect on the player that picks them up, thus allowing switches to be used without compromising gameplay. Furthermore, if you want to implement effects, you can make them to your liking, more so than the other orbs allow in the gametype settings.


[aname=8]Static is Sad[/aname]

A. Switches

Goody goody gumdrops, how I love switches, they appeal to my perfectionist side, since generally the creatively complex ones require precision to execute.

I believe ingenuity lies in using what you're given to accomplish what you want. Forge is beautiful in that it is so inexplicably lacking, forcing problem-solving to be a desirable trait in map-making, as such switches that accomplish novel things, such as transportation and dynamic environmental shifts, are praised as magnificent.

Some people take such statements as an invite to go on and add a switch for the sake of showing off their ability to copy someone else's design. Do NOT include superfluous things in your map. Triviality for the sake of arrogance is rivalled only by arrogance in the name of ignorance. Gimmicks are horrible and the source of inevitable criticism. Your switch must have purpose, must accomplish something that normal means cannot. Do you really need an elevator? A mancannon can accomplish the same thing at a fraction of the cost.

Switches are nice, but saving the budget is not only more effective, it allows you to do more with what you're given. Saving that extra $40 can add a room, or extra barrier, or just give you more confidence that you can use all of your ideas before the game limits them.

B. Events

Now, technically switches fall into a superordinate category known as events, which are preset situations that can either be player activated or set to coincide with a certain point in the respawn time. General timed events are most efficient when used to move player action forward. Examples include Killballs planted at the human spawn (in a linear map) after a set amount of time, or opening a door ninety seconds into the game, leading players into a notably safer area. Furthermore, they can be used in this regard as direction markers, such as exploding cars marking player progress through the map at every thirty second interval, such a use also doubles as a fine aesthetic piece. Simply put; be creative.

C. Teleporters

Teleporters, like switches, should be used when a discretionary budget allows as they cost four times as much as other objects in the forge list. Furthermore, such items need to be used in specific instances where it would be significantly cheaper to do so than manually build a pathway. The reason I use "significantly" is that, as mentioned throughout this piece, you don't want to break immersion, which using teleporters almost always does, one second you're in one area, then you're thrust into some other forced perspective.

Most importantly, teleporters cannot break gameplay, remember my bit about balance? Yeah, that still applies. The problem with teleporters is that, for the view-shifting reason mentioned above, they are very campable. To solve such a glaring issue, you should place teleporters on the zombie side of things (if the two teams are separated when it comes to spawning) so that humans cannot go through them, block and camp them.

If you want to be particularly devious, or must put the devices in the middle of the human path, place them in the air (to prevent blocking) and in strategic locations (to prevent camping), possibly resulting in paranoia-inducing ambushes.


[aname=9]Campground vs Freeflow: Burning the Tent[/aname]

In true guide-writer fashion, I'm going to generalize infection maps so that you truly know what you are doing rather than combining mixed elements of different maps and thus ruining the gameplay. There are two basic types of infection maps:

A. Camping

Oh, woe is he who plays games sans glee. That is me, and nearly every person who generalizes the infection genre based on their horrible experiences with the stereotypical camping zombie map. Makers of such maps should have a special circle of the inferno reserved for them, a place not even Virgil will delve into, so dark and annoying, so filled with glitches Forger's will have waking nightmares of the instant respawn deathzone.

I'm talking about imbalanced camping maps. People believe they can make a map filled with armories, a great camp spot, and it is still going to be fun. It could be, for the humans. Nothing is more annoying and boring than being the infected on such maps, forced to lend themselves to multi-kills on a repeated basis with the vain hope that they'll break through the seemingly impregnable fortress.

Remember, to keep people playing your map, you need balance, incentive, you need to make sure the humans are just as likely to get killed as the zombies.

This is a guide, so I can't very well tell you exactly what to do. I can, however, lay down some law.

• If there is an armory on this map, make it uncampable and put it near the zombie spawn or far away from any camp areas, or it will effectively overpower the opposition.
• Do not have a single entrance to a room if you need to jump up to it, crouch down to get through, or any other motion-limiting movements as it places the advantage in the humans favor by some factor I cannot quantify.
• Do not have a single entrance to a room if you have unlimited ammo enabled, otherwise there is no logical reason to the leave the area and compromise safety (that is BAD).
• Long rooms are horribly inadequate. They are unfair for the infected and tend to drag the game on longer than should be allowed.
• Use round limits for the same reason as the previous point.

Now that the foundation has set, here are some positive/negative aspects of this type of map.

The main upside to making maps like this is that its nostalgic for Halo 2 customs players and is a great introduction to the genre for novices. It isn't that hard to look for weapons and hold out in an area. However, since its that simplistic, it tends to get boring quickly unless the players are having to constantly check corners for possible break-ins to their location, thus, have multiple entrances and incentive to move about.

B. Walking

This type of map may be split further as well. Linear and open-world.

Linear

Linear maps employ a set path for gameplay, the player encounters happen along a set path and there is usually a goal to reach, such as a super-armory (which I highly advise against) or a safer area. These are especially easy to design for novices, an idea I gathered by the prevalence of the horrific "Fat Kid" maps, but require a lot of critical thinking to make them enjoyable.

The most challenging aspect behind designing such maps is keeping players moving forward. There are only so many killballs to put down behind players, so many custom power-ups to place ahead as motivation. One idea I'm employing in my current map is what I like to call the breadcrumb approach.

1. Limit player ammunition.
2. Intersperse weapons throughout the path, leading towards the end goal, sort of like Hansel's foiled idea to find his way back home in the Brothers Grimm tale.

It is simple and it works.

Open-World

This is essentially a mix between the camp-based maps and their linear-path alternatives. Players spawn in an open environment and can make their way through as they please.

A flaw I tend to find in such designs is that there are specific areas that become camp spots, and soon the "open-world" design becomes a race to a select few locations. Such places include hard-to-reach areas that humans can get to moments from spawn and stay there until the round is over, and small, enclosed "gun shops" off in some corner of the map.

I realize it is really hard to balance the areas and make them all desirable in their own right, but its necessary, otherwise the rest of your map is a trivial add-on for aesthetic effect. What I advise is using a counter-measure method.

1. At the basic level, design the map from a human-player perspective, make spots extremely fun to play if you were alive.
2. Purposefully put flaws (in the structure sense) in the design. Take out a ceiling-wall, put in an extra doorway, open the room, etc.

Furthermore, timed events on such maps can be extremely useful in making your players move around. Make a grav lift spawn in some room that pushes them out 60 seconds into the game, making that place a horrible spot to camp if zombies are around. If you're feeling rather unmotivated, just put a killball in a room. Sure it'll piss off some players and make others laugh, but they'll know to get out of there next time.


Keeping Common Sense

For those of you who need a reminder, or literally just scrolled through this because you hate reading and don't want to learn anything at all:

• Be creative
• Use common sense
• Rely on realism

If community needs dictate that I write a guide on gametypes I might, just didn't now since this is meant to help map-makers based on the Save One Bullet gametype for the contest. For now, if you have any questions/comments about the guide, or you'd like to see certain questions answered in a future guide, post them here.

Hope it helped.

-Sarge