RL Terrain

By R.Dan Henry (wikied by abcgi - with permission) (And now slightly improved for the web by the original author.)

Inspired by the "Of bottomless pits and invisible walls" thread awhile
ago, I did some thinking about the types of effects different types of
"terrain" can have in a roguelike. Of course, as usual with such
lists, using all of these effects in one game would be... well,
probably too much of a good thing. Possible example applications in
parentheses.

Movement Effects:
	normal movement (default)
	slows movement (mud)
	speeds movement (faerie path)
        blocks incoming movement (wall)
        prevents outgoing movement (tar pit, bear trap)
	randomizes movement (oil slick, ice)
	teleport (typically a trap effect, often a "terrain" in RLs)
	changes level (trap door)
	movement is more or less tiring (increases hunger rate or use
		of fatigue; likely an alternative to speed changes)
	modifies stealth (squeaky floor, pillows)

Character Effects:
	causes damage [amount, type] (lava)
	causes status changes (desert makes you "overheated", tall
		grass makes you "hidden" if small)
	grants experience (first time on terrain is a new experience)
	drains stats, experience, fatigue points, etc. (unholy ground)
	increase/decrease hunger, thirst, regeneration rate(s)
		(desert increases thirst counter rate)
	racial (or class) bonus/penalty (Elf gets +10 to actions in
		forest terrain, Rogue get +10 on city street terrain)
	religious influences (piety does not time out for worshippers
		of Sea God while on ocean terrain, prayer bonus on holy ground)

Item Effects:
	destroys items (lava, ice)
	(dis)enchants items (mana node)
	curses/blesses item (holy ground)
	damages item [corrosion, mildew, durability points lost]
		(swamp terrain makes scrolls mildew)
	polymorphs item (lava cooks dropped food, ice turns potions
		to frozen potions)

Combat Effects:
	improve/decrease evasion or attack (mud reduces evasiveness)
	blocks missiles (wall)
	hinders missiles (firing through brush reduces chance to hit)
	aids missiles (firing into death zone terrain doubles damage)
	destroys missiles (firing over lava destroys arrows)
	special effects (if hit on ice, chance to slip and fall)
	elemental attacks influenced (ice bolt over lava loses
		strength)

Other Effects:
	block LOS (wall)
	self-illuminating (lava)
	subject to change (dry grass may burn, low ground may flood)
	encounter types (monster, item generation keyed to terrain)
	obvious or not (quicksand and traps hidden)
	summoning effects (brambles produce ticks)
	spell-casting boni/penalties/mods (healing is more effective
		on holy ground)

These effects can be automatic, optional (set off/avoid known trap),
allow a saving throw or skill roll of some kind, or vary based on
factors like species (spiders on webs), movement mode (flying over
mud), intrinsics, items, statuses (drowning may depend on burden
status) or skills (if you have Swimming you don't drown). Some of
these suggestions are fairly exotic, but could be just the things for
the right game.

R. Dan Henry
danhenry@inreach.com