This chapter is about how a character’s progress is impeded by barriers, obstacles, and detectors. It contains the following sections:
I use the term barrier to describe something that prevents a character’s movement or advancement—generally something physical that stands in the way or something on a game map that is impassable. However, there can be exceptions to that rule, such as a post-hypnotic command that prevents advancement or an illusory barrier of any kind. Barriers are used often to define an area and its entrances and exits. They can be permanent features of the game environment, or they can be transitory. Barriers can be affected by the player’s actions or not, depending on their use.
Although it is a subtle distinction, I define obstacles differently from barriers. All barriers are obstacles, but some obstacles are not necessarily barriers—though they are, by their very definition, challenges. While barriers present challenges to movement, obstacles can impede any sort of progress, even where movement is not necessarily the primary purpose. Put another way, obstacles prevent you from doing what you want or intend to do. Although barriers often serve that purpose admirably, other obstacles might exist, such as legal, moral, or ethical considerations, people who try to prevent you from performing your tasks, or even something as simple as a traffic jam that slows you down.
Barriers can often be an impediment to the player’s progress—something to be overcome—but they also serve strategically to the advantage of players, depending on the situation. Thus, a castle wall is a problem to be overcome if you’re attacking the castle, but it is a great help to the defenders.
Barriers won’t always stop your progress all together. Some barriers will simply slow you down or otherwise make progress more difficult. I call these hindrance barriers. In essence, if a barrier doesn’t absolutely stop you, it can:
For instance, a poison gas field will poison the character, but it’s possible that the character will still make it across. An oil slick or ice field might make the going more dangerous and more difficult to control, but you can still get across. Deep mud can slow you down, but it probably won’t stop you. In some games hot lava is deadly, but in others it can be passed, though it often causes damage. A minefield is only dangerous if you trigger a mine, and a barbed-wire barrier is passable if you are careful, but it will slow you down considerably. An open area with no traps or other features can still be a barrier if it is protected by snipers or subjected to artillery fire. These types of barriers are more in the nature of impedances rather than absolute barriers.
Besides hindrance barriers, some barriers stop you, but only partially, so I call these partial barriers. For instance, you can see into a space and maybe even throw or shoot something into it, but you can’t enter. A window is an example of a partial barrier, where you can see through it but you can’t enter without breaking it. Likewise, bars (such as a prison cell) would be a partial barrier because you can see and hear through them and even reach your arms through them. Or consider a magnetic field that allows organic matter to pass but prevents any metal from getting through, or even those detectors that sound an alarm if a shoplifter attempts to leave with a package that hasn’t been properly checked out.
This segues nicely into a specific type of barrier that is based on detectors. Detectors can be used to prevent passage, operate various devices, and otherwise make life difficult for players. Detectors are covered in a separate section (“Methods of Detection”) later in this chapter.
Barriers can be fun. They always serve a purpose—to prevent the player character (and sometimes NPCs) from going from A to B, or at least to make it more difficult. They often serve to alter the player’s route, but sometimes they serve as challenges to overcome. At any rate, games that involve physical movement in a space always have some kinds of barriers, whether it is simply walls to contain the action or something more elaborate.
Openings—doors, gates, windows, turnstiles, portholes, air locks, etc. Any way to enter or exit a location that can be latched, blocked, or locked.
Natural barriers:
Mountains
Steep canyons, rifts, crevasses, cliffs
Rivers and canals
Oceans
Lakes
Swamps
Forests
Thickets and briars
Fallen trees
Quicksand
Boulders
Cave-ins, landslides, and avalanches
Storms
Snow and ice
Thin ice
Sticky mud
Rapids and waterfalls (especially for boats)
Shallow water, sandbars, reefs, ice for boats
Animals (packs of wolves, army ants, etc.)
Fire
Fallen buildings (rubble) and/or crashed or wrecked cars/trucks, etc.
Fences:
Barbed wire
Electrified
Tall
Spiked
Chain link
Wooden
Picket
Bamboo
Brick
Concrete
Wooden
Stone
Metal
Barbed-wire, glass- or razor-topped
Mazes:
Tunnels and underground
Hedge mazes
Inside buildings
Surreal environments
Traps:
Spikes
Explosives
Trapdoors
Teleporters
Electrified or other damaging barrier
Projectile trap, auto-firing (crossbow, shotgun, giant spear, poisoned darts, etc.)
Enemies (bad guys, aliens, killer robots, etc.) blocking a path.
Enemies of a higher level than the player can yet handle. This is a way of controlling pacing and player advancement in many games, particularly Massive Multiplayer and Role-Playing Games, where zones and areas are populated with increasingly difficult enemies, and the player can gain access to those areas only when he is strong enough to deal with the threats they contain.
A herd of large or dangerous animals (such as cows, elephants, or wildebeest).
Other dangerous creatures, such as piranhas, stinging jellyfish, or a flock of mad crows.
Black hole or warp field.
Meteor cloud.
Gas or poison cloud (or vacuum).
Toxic waste (radioactive, industrial, etc.).
Force fields.
Pile of bodies (or just one body blocking an opening).
Invisible disorientation beam (such as certain sonic beams that can cause a variety of disorientation [and physical] effects).
Police barrier.
A car crash or overturned bus or truck.
A minefield.
Spikes in the road, caltrops, etc.
Artillery fire or a line of tanks.
Hidden entrances/exits or hidden mechanisms to open/close.
A giant airbag.
Slippery conditions (natural or manmade).
Lack of food or water. (For instance, a desert where someone will die of thirst if they try to cross. Also, an area without the ability to feed an advancing army is a barrier to that army.)
Barriers can be defeated by various means. In this section, I’ll provide a few examples of common types of barriers and how to get past, through, or around them.
A mountain range could be defeated by:
Flying (airplane, hot-air balloon, hitching a ride on a large bird, etc.)
Secret pass (over or under)
Teleportation
Going all the way around
Changing the molecules in your body so you can walk through solid matter
Blasting a tunnel
Getting really big and stepping over it
Getting really big and crushing it
Nothing—may not be passable (used as a border on a landscape)
A high wall could be defeated by:
A ladder
A ramp
A pile of boxes/barrels
Someone to help you climb
A rope and grapple
A subtle hand/foothold (rock-climbing metaphor)
A trampoline
Springy shoes or a high-jump ability
Stilts
A sledgehammer
Explosives
A friendly rhinoceros
A secret door
A bazooka
Going around
Tunneling under
Tentacles that lift you over the wall
A locked door could be defeated by:
A key
Lock picks
A battering ram (or strong shoulder/kick/axe, etc.)
Explosives
A helpful NPC who can unlock it
Magic (an open-door spell, for instance, or a teleportation spell)
Transformation, such as turning into a mist and drifting under the door or through the keyhole or becoming able to pass through matter
Getting someone inside to unlock it
Traveling to the future or past when it wasn’t locked
Burning it
Ramming through it
A force field or other trap could be defeated by:
Turning off its source of power
Coming up with a suit or item that nullifies it
Note
There are lots more ways to defeat a force field. To avoid repetition, I suggest you check out the “Methods of Detection” section later in this chapter.
A pile of stuff (boxes, barrels, rolls of wire, old dolls, and so on) could be defeated by:
Burning it
Breaking it
Restacking it
Scattering it
Getting something to eat it
Using acid
Using weapons and/or explosives
Driving something through it
Using magic spells
Getting an off-duty garbage man to take it away
Blowing it up
A police roadblock could be defeated by:
Ramming it and driving through
Going in disguise
Going around it
Becoming invisible
Infiltrating it (as a policeman)
Flying over it
Tunneling under it
Finding another path
Blowing it up
Causing a diversion—such as a nearby fire—and sneaking past
Taking a hostage
A chasm or rift could be defeated by:
Flying over it
Building a bridge across it
Using magic (many options, ranging from teleportation, to super jumping ability, to flying, to conjuring a creature to carry you)
Climbing down and back up
Finding a secret path
Jumping it in a vehicle
Hitching a ride on a passing bird
Hang-gliding over
Using a rope and grappling hook to make a tightrope and crossing on it
Relying on an earthquake that closes the rift
Nothing—it may not be passable
A massive storm could be defeated by:
All-weather gear
Weather magic to counteract it
Flying over it
Going underground or underwater
Waiting for it to pass
Changing the environmental or enemy-made cause of the storm
Conjuring a storm elemental to control it
Teleportation
Passing through and hoping for the best
An enemy group or army could be defeated by:
Another group or army
Superior weaponry
Divine intervention
Magical attacks
Illusion
Distraction
Infiltration or disguise
Going around it
Sneaking through it (stealth)
Capturing the leader and holding him hostage
Capturing a messenger and sending in false orders (to move, to let you pass, etc.)
Sheer tenacity
Waiting for the enemy or army to move on
A group of dangerous animals or a herd of large creatures could be defeated by:
Distracting them with something else they will attack
Spooking them so they run
Sneaking among them (disguising your scent, perhaps, or being invisible)
Going around
Morphing and becoming one of them
Luring their natural enemies among them
Destroying them somehow
Waiting for them to leave
Feeding them
Charming them
Taming and riding them
Games generally impose limits on a player—how high can you jump or how fast can you run, for instance. Games also generally impose limits on a player’s movement within the game environment, but if the limits are believable, they enhance the sense of reality of the game. There are several ways to create limits to travel and movement:
Natural Barriers. Natural barriers are often displayed on maps with recognizable textures or tiles (on tile-based maps). Players learn very quickly that these areas cannot be crossed.
Water (large body—surrounding an island or at the edge of a continent).
Water (flowing—impassable rivers, for instance).
Mountains.
Creatures (such as sharks or piranhas in the water or killer bees on land, etc.).
Dense forests.
Deserts.
Chasms and cliffs.
Landslides, large boulders, etc. (You may be able to pass these later when you find the dynamite or learn some useful new ability or spell.)
Manmade Barriers. Note that some of these are not absolute barriers, but may be impassable at certain stages of the game.
Bridges (broken, guarded, or raised).
Military zones. (Shot on sight?)
Guards (won’t let you pass).
Force fields.
Landmines.
Barricades.
Auto-turrets (will shoot you).
Indoor Barriers:
Locked doors/barred windows, etc.
Walls.
Gates that cannot be opened.
Guards (human, animal, or other).
Detectors.
Traps.
Secret passages. (The entrance is hidden.)
Treacherous paths—jumps, narrow pathways, high places, moving platforms, toxic conditions, etc.
Configuration and sequence puzzles. (See the “Configurations” section in Chapter 27, “Puzzles.”)
Psychological pressure/threats.
Illusions. (The character is somehow made delusional.)
Intolerable sounds.
Force fields.
Cells (as in jail/prison).
Walls.
Collapsed areas.
Game Mechanics. Although there are many believable and realistic ways to limit movement, there are some that are simply convenient but not part of the realism of the game, such as:
You reach a place where the game asks, “Do you wish to quit the level?”
You receive a message saying, “You can’t go there.”
You try to move forward but hit an invisible and unexplained barrier, even though you may be able to see a landscape stretching into the distance.
Teleporting the character to the same area or an undesirable area.
While barriers are always obstacles that prevent movement, this section looks at some other ways your progress can be impeded.
Obstructionist NPCs. Someone who won’t let you proceed or give you what you need until you meet certain conditions.
Phobias. Fear of snakes, height, outdoors, confinement, and so on. See also “Phun with Phobias” in Chapter 12, “Character Design.”
Post-Hypnotic. A command preventing a character from advancing.
Law. This applies to a character who can’t or won’t do anything illegal.
Morals or Ethics. This applies to characters who can’t or won’t violate certain value systems.
Ignorance. You have a lack of necessary information.
Size. You’re too big or too small to accomplish a specific task.
Missing Equipment. You lack some necessary items, such as a key to unlock a door or chest.
Missing Skills. You lack the necessary skill—such as lock-picking when faced with that locked door or chest for which you lack the key.
Other Players. Competitive or even cooperative players can act as obstacles either intentionally or unintentionally.
Distractions. You are tracking too many simultaneous events, or some emergency requires your attention.
Physical Restraint. Something holds you physically and prevents you from moving or advancing.
Threats. You are prevented from acting because of threats to yourself or others.
Blackmail. Blackmail is a specific kind of threat, which may involve harming others or revealing secret information about you that you don’t want known. Someone can use blackmail not only to extort something of value from you, but also to control your actions, which makes it an obstacle to your progress.
Physical or Mental Incompetence. It’s always an obstacle when your own body can’t do what is necessary or your mind cannot deal with the issues at hand. If you are too weak to move a large stone, it’s an obstacle. If you are Hercules, perhaps it’s not. If you don’t have the mental powers to decipher a code, it’s an obstacle. If you’re some kind of brainiac, it may be nothing more than a momentary annoyance.
Devotion. You cannot proceed if someone would be left behind.
Many obstacles, barriers, and traps rely on detecting the player’s movements and activities. Methods may vary, from high-tech invisible laser beams to a simple string with cans tied to it to make noise if someone walks through the string—and just about anything between these two extremes. In this section, I’ll present a few ways to detect someone, with some suggestions for how to get past them. This is just a partial list, so there’s plenty of room to innovate and come up with your own detection methods.
Breaking a light beam can be defeated by:
Timing the sweep of the beam
Crawling under or gliding over the beam
Fooling the beam with a special non-reflective suit or other cloaking system
Moving really slowly
Using acrobatics to get around the beam
Movement sensing can be defeated by:
Moving very slowly
Crawling under or gliding over the sensor’s area
Wearing a suit that cancels out the movement sensor
Teleporting or using astral (non-physical) travel
Sound sensing can be defeated by:
Moving very quietly
Crawling under or gliding over the sensor’s area
Wearing sound-canceling clothing
Creating a sound-canceling device to fool the sensor
Infrared (heat) sensing can be defeated by:
Freezing yourself
Wearing a cold suit
Transforming into a reptile
Radar can be defeated by:
Avoiding the radar
Wearing stealth gear
Fooling the radar with false signals
Jamming the radar
A guard seeing you can be defeated by:
Keeping to the shadows
Wearing a disguise
Disabling the guard
Being invisible
Creating a diversion to distract the guard
Tricking the guard (preferably without setting off alarms)
Distracting the guard
Killing the guard
A remote camera can be defeated by:
Staying in the shadows
Timing the sweep of the camera
Destroying the camera
Patching in a fake image to display a false image on the monitors
Staying out of the camera’s range
Conduction changes in an object as you touch it can be defeated by:
Wearing gloves
Using a nonconductive device to manipulate the object
Using telekinesis
Change of weight on a platform can be defeated by:
Replacing the object quickly with something of equal weight
Jamming the platform to prevent it from moving
Freezing the platform
Shadows being detected over the item can be defeated by:
Moving so that your shadow doesn’t hit the item
Shining a light to compensate for the shadow
Using an implement that doesn’t cast a shadow
A little switch under the item popping up can be defeated by:
Sliding something under the item to keep the switch from popping up
Freezing the switch to prevent it from moving
For all electronic devices you can also do the following:
Break/destroy the item.
Using EMP (Electro-Magnetic Pulse) to disable the detector.
Hack the detector to use it to your advantage.
Take out the power grid.
Design Challenge
Each game, each project, and each situation is different. However, how often do you simply come up with the most obvious solution when you need to limit the player’s freedom of movement or erect a barrier of some sort? This design challenge has several parts:
Think of barriers you have created or barriers you’ve seen in other games and come up with at least three other types of barriers that could have been used in those situations.
Think of at least one type of barrier or detector not listed in this chapter. Even if you can’t think of one, the exercise will stimulate your creativity. Now design a way to use this barrier in a game situation, or, if you didn’t come up with anything new, consider whether you could create more interesting barriers now, based on what you have seen here.
For each of the following environments, come up with at least three types of barriers or detectors, and how they would function in the game:
A city street
A freeway
An office building
A mountain pass
A river or lake
A prison or jail
A mental institution
An enemy stronghold
A tunnel or cave
An outer-space adventure
A military engagement
An individual’s race against time (on foot? in a land vehicle? in an aircraft?)
In your own designs, what kinds of barriers will you use? Try discarding your first thought and coming up with something else. Does that change the game and give you some new ideas? Keep substituting different ways to control the player’s freedom or movement. Think of some unique methods.
Think of the kinds of detectors you’ve encountered in the games you have played. List them and then list the ways you got around them.
Can you think of any other types of detectors, or possibly some unique ways to use them?
Write down some specific applications of some of the detectors. What would the scene be exactly? Where would you use detectors and what would they do? How would your player’s character get around them?