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§10.8. Fire

Fire exhibits some of the properties of a gas: it is only vaguely located and tends to spread out, though it passes by touch rather than on the air. It is hazardous to life, through direct contact, heat, and smoke. Better governed, it provides light and warmth. Worse governed, it consumes almost anything it comes into contact with. Here the problem with "debris" is not so much that we need potentially hundreds of new objects to represent broken items: instead, fire could sweep through a work of IF destroying so much that no play is possible any longer. Setting up a problem in which the player must defeat a fully-capable fire is difficult to balance.

As with liquids, it is best to simulate the least amount of fire that the design will allow. Bruneseau's Journey provides a single candle which can be lit, or blown out, but where fire can never transfer from the candle's end to anything else - or vice versa: the player's source of fire, with which to light the candle, is discreetly neglected.

In the more realistic Thirst 2, a campfire is lit using a tinderbox, so that fire does transfer from one thing (tinder) to another (the campfire): but it is always confined to just these two items, and can be used only for light and warmth.

The Cow Exonerated provides a class of matches that can light any flammable object, but assumes that burning objects requires only one turn; lighting one thing does not burn another.

In Fire or in Flood provides a complete simulation of what we might call "wild-fire": combustion which spreads through arbitrary objects and rooms, destroying all in its path.

* See Examining for a way to describe objects as charred once they have been partly burnt

* See Heat for one consequence of fire having touched something

* See Gases for an implementation of smoke without fire, if this can exist

* See Liquids for water being used to extinguish a simple fire

* See Lighting for other uses of candles and torches as light sources

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*ExampleThirst 2
A campfire added to the camp site, which can be lit using tinder.

**ExampleBruneseau's Journey
A candle which reacts to lighting and blowing actions differently depending on whether it has already been lit once.

**ExampleThe Cow Exonerated
Creating a class of matches that burn for a time and then go out, with elegant reporting when several matches go out at once.

***ExampleIn Fire or in Flood
A BURN command; flammable objects which light other items in their vicinity and can burn for different periods of time; the possibility of having parts or contents of a flaming item which survive being burnt.