Luceat Lux Vestra - Making Light Management More Interesting in Old School Games.

LIGHT IN THE DARKNESS

In the dark gulfs beneath the earth, the ancient places where thick darkness wells up a hungry oil of ebon malice the greatest weapon of the brave explorer is not sword or axe, but light.  Each guttering torch and cheap tin lantern is a tiny fragment from the world above, a piece of the sun. Without light the soft creatures of the overworld have no hope; the sharpest blade cannot cut the horror it doesn't see, and the stealthiest pilferer cannot find the bright gold and jewels concealed in the gloom without a telltale glimmer.

THE OLD SCHOOL BASIS

Looking through the old 1974-79 edition of Dungeons and Dragons (Original D&D or The Little Brown Books) one finds an interesting passage about dungeon exploration on Underworld Adventures, page 9 about lighting and surprise. A pair of short paragraphs are the only mention of how light works as a rules mechanic in the Little Brown Books, though torches, lanterns and oil flasks are mentioned as items for purchase (though without a given encumbrance weight).

"In the underworld some light source or infravision spell must be used. Torches, lanterns and magic swords will illuminate the way, but they also allow monsters to "see" the users so that monsters will never be surprised unless coming through a door. Also, torches can be blown out by a strong gust of wind. Monsters are assumed to have permanent infravision as long as they are not serving some character." Underworld Adventures, Page 9, Gygax & Arneson (1979).

William Blake, 1794 - A standby for creepy game imagery

A second short paragraph reiterates the surprise rules a bit down the page.  These rules are interesting in that they assert a necessity of light sources for dungeon exploration, assume infravision is a spell (and so a limited resource) and radically change the way encounters run in the underworld, because the party cannot surprise its enemies unless they are opening a door, and monsters still have the 1/3 chance of surprising the party.  When getting the drop on explorers monsters will almost always attack under these rules so light sources balance out the relatively generous reaction roll table.

Yet these rules don't discuss visibility range, light source exhaustion or anything else beyond how light effects the denizens of the depths. However the rules in Underworld Adventures do remind the reader that light works as a two way interaction, the underworld can see well illuminated players long before the players can see the creatures of the depths.

NEWER INFLUENCE

I am not really that beholden to old school D&D, and there's plenty of good ideas about how to run tabletop games that have come along in the past forty years and expand on the sparse and clumsy beginnings.  One game that I don't especially love (though I've only played it once) was Torchbearer, my complaints were with the implicitly vanilla fantasy world that seemed baked into some of the rules, and the Storygame tendency to reduce player creativity and problem solving to simplistic min-maxing mechanics through a bonus stacking system.  Yet, Torchbearer has some neat rules about supply and resource exhaustion, with abstract turns that rapidly eat up light resources and clear status effects as a result of being lost in the darkness. 

Building off these ideas, some members of the online old school game community (principally Brendan over at Necropraxis) have come up with an expanded Random Encounter die that I like to call an Exploration Die, and that includes not only the chance to encounter wandering monsters or environmental hazards, but acts as a random check for resource exhaustion (light, hunger and long-term spell effects).  This has the advantage of removing time tracking as a burden on the GM, and I find it both useful and fun in a less heroic fantasy setting.
A strict encumbrance system based of significant items slots (number of items carried is equal to character strength) helps make the choice of what equipment to big into the dungeon meaningful, as taking one item usually requires leaving another behind.  This means that the decision to bring enough torches or lanterns is a meaningful one, and that there is a possibility of exhausting a party's light supply even in a short session.  Additionally, equipment will need to be abandoned to make room for treasures. These rules also have the advantage of being harder to misuse then a weight based system, and are much much simpler to track.

PURPOSE OF LIGHT RULES

One of the strong design elements of old school tabletop games is a paucity of rules, allowing player and game master creativity to flourish and rulings on an ad hoc basis.  This is sometimes presented as a negative in that it allows poor social dynamics at the game table to ruin the game (an adversarial GM or a GM who isn't willing to make harsh calls coupled with an overly demanding and pushy player for example), but simplification and ad hoc rulings also prevent a dependence on rulebook minutia/trivia/loopholes and fewer rules allow for a simpler game.  With the design goal of maintaining simple flexible rules and faster play, tinkering and house ruling is always a risk - adding complexity should serve a purpose.

Here the game I want to play is one of resource exhaustion and player decision making about not only the optimal way to solve problems, but what resources to bring to bear on a specific problem and a sense of never having quite enough equipment to always do things the easiest way.  Strict encumbrance rules are needed for these light rules to be more then a mild annoyance, but assuming one wants to run a resource exhaustion/management game (really the basis for an exploration rather then combat or storytelling game) encumbrance will already be an important element of the game.

The light rules should then encourage player choice and create a risk and reward set up if they're going to improve one's game, and that's the primary goal here, something that doesn't add much complexity, makes a bit of intuitive sense, minimally effects established game mechanics and increase meaningful player decisions.

LIGHT STATUS

Darkness: In the underworld the darkness strangle even hope.  Without light sources overworlders, no matter how skilled or resilient are utterly lost, and were explorers not enured to the terrors of the black depths they would likely go mad after a short time in the absolute darkness of the underworld.  The darkness found beneath the earth is not like normal darkness, it is a nightmarish almost sentient presence that clings and tugs before closing in completely.
 
The majority of the underworld is dark, from block built stone tombs to vast underground caverns.  Unless otherwise noted dungeon areas should be considered to be shrouded in darkness.

Dim: Even the tiniest amounts of light provide a profound change from the total gloom of the underworld. Dim light is discouraging and not optimal for most surface dwellers, but it does not create the complete physical helplessness and rarely induces the total mental breakdown that true darkness inflicts.  Some sorts of explorers are at home in dim light, have practiced and honed their skills skulking in the deep shadowed forest, slinking along darkened streets or scavenging and spying along the night shrouded no man's land between armies. Dim light is provided when there are too few light sources for the number of explorers and by certain smaller light sources (such as candles).

Ambient light sources do exist in the depths, most commonly bioluminescent lichens, fungi and creatures, but also the radiations of certain magically charged ores and minerals. Creatures of the darkness that use fire for heat and cooking (usually by burning bones soaked in fat, volatile rock milk or coal), will often have lairs filled with dim light and some (such as the degenerate human strain of troglodyte commonly called "hole people") even find it comforting. 

Illuminated: Explorers of the underworld, unlike most over ground dwellers, are comfortable enough in the flickering lights of torch or lantern to function normally, however full illumination in the deeps is not without drawbacks, as light is alien to the underworld, and its residents are adept at spotting bright light from a good distance away.

Very few parts of the underworld are brightly lit, active volcanic areas and a few grandiose projects of underworld despots who use the hated mysterious light to show their glory and power. 

LIGHT  STATUS EFFECTS DURING EXPLORATION

Darkness:  In the darkness even the most skilled above ground explorer is at a grave disadvantage, capable of moving only by touch.  Total darkness prevents the use of all skills (such as searching or disarming traps).  Only the skills listen and stealth function in the darkness, and indeed is a character has been in total darkness for two turns previously the other senses try to take over for the eyes, providing a +1 (using an X in 6 skill system) to their listening skill.

Worse then the inability to use exploration skills, being lost in the darkness is both psychically and physically taxing and the inability to notice traps or obstacles until upon them provides a -4 to all saving throws or statistic based hazard checks.

Lastly the loss of light seems like a good time for a GM who has been drawing maps on a whiteboard or revealing a map with some sort of fog of war tool to stop, or even remove the prior map from player hands until they again find light. 

Another difficulty with darkness is that every turn it persists henchman must make a loyalty check to avoid wandering off, collapsing into a useless pile of anxiety or becoming lost (unless the party has intentionally doused their lights and is remaining in one location.

Darkness does allow explorers to surprise underdwellers (underdwellers can still surprise explorers as well) with a 2 in 6 chance.

Dim: Most from the surface suffer debilitating effects from functioning in dim conditions.  Without sufficient light is is still possible to perform complex tasks, but it becomes far more difficult.  All skill rolls are at -2 and are all saves or statistic checks. Thieves and rangers (or similar classes depending on setting) are skilled in dim conditions, having trained to stalk the shadowy forests, skulked among the gloomy streets or stolen into enemy camps across the no-man's land of a midnight battlefield.  These classes suffer no penalties in dim conditions, and gain some benefits if they are able to function without any bright nearby light sources.

Henchman are rarely as brave as true explorers and suffer from a -2 to all loyalty or morale checks if in dim light (unless they are thieves or rangers used to operating in such conditions). 

Dim light is sufficiently common in the depths, and sufficiently poor to allow explorers to surprise underdwellers if all members of the party are in dim light on a 1-2 (underdwellers may also surprise explorers). A thief or ranger working alone (or with other infiltration specialists) and operating in dim light gains a +1/+20% to their stealth skill, but only if they are at least 20' beyond the light radius of any companions who are illuminated.

Illuminated: While this light provided by flickering torches or oil lamps is not great, delvers into the eldritch gulfs beneath the earth are brave and skilled at functioning in these conditions.  There are no penalties associated with acting while illuminated, though groups with large numbers of blazing lights tend to stand out in the darkness. 

While Illuminated (or in a group that is at least partially illuminated) explorers cannot surprise enemies, unless they are opening a door and entering a room with enemies inside - or enemies are entering a room that contains the adventurers through a closed door. 

LIGHT STATUS EFFECTS IN COMBAT

Darkness: Darkness has an equally negative impact on the combat abilities of above worlders as it does on the ability to move and explore.  Combat rolls and abilities receive a 4 point penalty in the dark, including a penalty to armor class.  Only damage and grappling tests remain unaffected 
Targets in darkness (and beyond as light source - such as the 40' radius of a lantern) are impossible to aim missle attacks at.  Even underdwellers cannot target explorers in the dark, except from close range, and explorers cannot use missile weapons in the dark beyond reaction/reach or melee range (if the weapon can be used in melee).

Dim: It is difficult for most surface dwellers to fight properly in minimal light, attack go array finding an allies side and it's hard to see the enemy sneaking around the flank.  All combat rolls except damage and grappling tests are at a two point penalty, including armor class. Thieves and rangers who are skilled at functioning in dim light do not suffer these penalties (making them rather effective at killing other surface dwellers above ground).

Dim light also provides sufficient concealment to hide those in it from missile attacks beyond close range (from either surface explorers or underdwellers).

Illumination: No modifiers to explorer's combat abilities, and while some monsters may dislike or avoid full sunlight, the light of torch and lantern is not enough to penalize them.

Characters or underdwellers who are illuminated can be hit by missile weapons at any range that their light is visible (generally twice the light radius it provides).

LIGHT SOURCES

Various types of light are used by surface peoples to fend of the dark, from crude oily dried fish fitted with wicks to chemic arc lamps. For mechanical purposes these light sources can be roughly classified by the number of delvers they will keep in full illumination, and the radius of the light they shed, revealing underworld features and foes.

Torch – The bright light of an open torch flame illuminates up to three characters and provides dim lighting for up to three more.  While bright, the flicker firelight is random and distracting, obscuring as much as it conceals beyond 30’.  

Torches may be used to set fires, or light oil bombs.  In combat they are an improvised weapon doing 1D6/3 fire damage and if wielded in the off-hand their awkward nature means they provide no additional bonus for dual wielding. 

Lantern – Lanterns come in a wide variety of stules, but all use a reservoir of flammable liquid to create a steady and widely spread light, but are not as bright as torches.  Two explorers can be illuminated per lantern, and two more provided with dim light.  The lantern spreads light out in a soft pool 40’ in every direction, though many lamps are made with shutters to quickly dose them, filters or screens to dim them or a directional lens to focus them in one direction (a bulls-eye lantern).  For purposes of dungeon lighting all lanterns are deemed the same however.  Lanterns are generally contained and so cannot be used to start fires (unless thrown), they do have the advantage that they can be attached to belts, backpacks, helmet or other locations leaving the hands free for climbing (though this is not advised in combat as any strike rolling a 15 or above [even if it misses] will shatter the lantern dousing it’s carrier with flaming oil) unlike torches.  Lanterns may also be set down before combat and will continue to provide light (assume your players do this, characters are professional tomb robbing monster slayers after all).

Explorers often fill their lanterns with the same volatile oil that is used for military purposes and a lantern makes a decent ad hoc fire bomb when throw.  Lanterns will do 1D6/2 damage for the first round and the normal 1D6 the second, though unlike oil flasks they can only be targeted at a single enemy (burst value 1).
A lantern takes up one encumbrance slot, as does each refill/firebomb. They are longer burning then torches however and each flask of oil will burn for two light exhaustion pips on the exploration die.
Candle: Candles are any small, easily concealed light better suited to finding ones way to the privy without disturbing fellow sleepers rather than lighting a room.  Candles provide dim light for a single explorer and may be tucked in a hat brim, set in a miner’s helmet or wedged into the top of a backpack.  They are primarily used by thieves to scout while remaining inconspicuous.

Candles can light oil bombs and start fires.  Candles may be carried five to an encumbrance slot.
Fire Bomb: hurling firebombs is a time tested tactic in the confines of the underworld – fire and light are both terrifying and dangerous, and both explorers and intelligent underdwellers are often equipped with a variety of firebombs form crude Molotov cocktails to sophisticated binary rock milk and phostogene bombs or white phosphorous projectors. These weapons all produce a blast of light when they strike (even on a miss) providing illumination for all within 40’ for two rounds before guttering out.

‘Firebombs do 1D6 damage the first round and 1D6 damage the second, they can effect up to three targets each (burst value three), with each target saving vs. wands to end the attack (i.e. if the first target saves the bomb misses).

 Magic: Magical light comes in two basic varieties and numerous flavors from floating flames to rays of divine grace that can penetrate deep into the underworld.  Light spells (and other temporary magical light) are slightly more effective than a lantern, ranging 50’ in diameter and providing illumination for up to 4 explorers (and dim lighting for up to 4 more).  

Permanent magic light (or continual light) must be tied to a location, and no spell can be memorized over it until it has been extinguished.  This continual, immobile light is very strong however and will fill a chamber (or a 100’diameter circle – whichever is smaller) providing full illumination for all within its radius.
Generally magical light will not start fires.

UNDERWORLD DWELLERS

The denizens of the underworld can see just fine in darkness, dim light or illumination (though it feels a bit uncomfortable for most).  They are inhabitants of the pit and have been used to darkness from birth.  To underdwellers light is the intruder and strange inversion of all that is good and normal.  The distaste of light (though they will use fire for cooking and light for decoration) is what separates true underworld creatures from those who merely inhabit surface caves or old ruins.  The races of the deep are almost as afraid of the terrestrial surface, it’s bright sky and blazing eye-like orb as most surface dweller are afraid of the deep chthonic darkness of the underworld, and only the bravest underworld heroes will venture into daylight to seek the mysteries of the overworld.  Indeed, underworld dwellers suffer a -2 to all rolls and AC in full sunlight (except those who are wearing dark glasses, veils or large shade creating hats).  

Worse though for the underworld horror stranded on the surface, the underworld nations find missile weapons of limited utility, and rarely use them beyond thrown weapons or the odd flat trajectory bone and sinew bow. The armies of the surface and their long range siege engines, arcing high angle longbow archery and cavalry maneuver are almost unknown in the underworld (just as military tactics of the deeps are a mystery to surface powers). This is what keeps the membrane between surface and deeps so strong,  the powers of the dark cannot properly invade the powers of the light, nor can the surface march upon the polities of the deep.  

SPECIAL VISION

It's traditional in some versions of tabletop fantasy games for demi-humans (Dwarves, Elves and Halflings/Hobbits) to have 'infravision' or 'darkvision' and thus the ability to peer long distances into the underworld without the use of light.  I don't find these rules helpful at all, it's another powerful ability for demi-humans, that makes little sense within the construct of the 'mythic underworld'.  Certainly a creature of field and meadow like a traditional vanilla fantasy halfling, loving it's warm comforts and cellars full of cheeses doesn't sound like the sort of creature that should be able to move in the deep places of the earth with the speed, stealth and aclarity of an eldritch horror born of the black depths - but with night vision at twice the range of a torch the humble halfling is an incredibly dangerous underworld denizen.  Likewise the elf, though perhaps something about staying up late in in the dark forests to sing endless sad epics could account for the ability to see in the dark.  Dwarves, with their stone halls and mining make the best case for moving easily and efficiently in the underworld, but again I want to draw that sharp distinction between the terrestrial over-world and an underworld of strange and reaching gloom.

Regardless of what demi-human races are setting appropriate, darkvision will provide some amazing benefits that allow it's owners to instantly become the best scouts in a party, detect enemies form long distances and give them additional encumbrance slots.  As such I would either limit darkvision to something akin to a thief's ability to function normally in 'dim' conditions or place penalties of creatures with darkvision who seek to act while illuminated.  For example, if one were to replace halflings with goblin player characters (a popular setting decision in some circles) and wanted to give them dark-vision, making goblins act and fight at a -2 in conditions of daylight or full illumination seems appropriate.  That might give the party a great stealthy character underground but it will be one that needs to wear a very broad brimmed hat outdoors and bumps into trees every now and then. My own impulse is only use player races (unless one provides a considerable offsetting penalty to the class) that lack dark vision, and limit the number of magical items granting enhanced vision very carefully, because otherwise one might as well going back to ignoring light sources as a resource management concern.