
====== The Dungeon ======

     All levels other than 0 (the town) lie within the dungeon.  Each level
of the dungeon is fifty feet high, and is divided into large rectangular regions
(several times larger than the screen) by impenetrable walls.  Once you leave a
level, you will never again find your way back to that region of that level, but
there are an infinite number of other regions at that same depth that you can
explore later.  Monsters move about just as you do, and you may see them again.


--- Terrain ---

Rubble:
     Blocks movement, but is relatively easy to dig through.  Rubble may contain
hidden objects.

Permanent walls:
     You can dig through most walls but some are impenetrable.  The dungeon is
surrounded by these kinds of walls and some special rooms are made of them.

Staircases:
     Staircases allow your character to ascend or descend from one level to
another, and are represented by white "<" (up) and ">" (down).  Each level has at
least one up staircase, and two down staircases, unless it is the home of Sauron
(level 99/4950') or Morgoth (level 100/5000'), whom you must kill before
staircases will appear.  Otherwise, the staircases are guaranteed, but they may
be difficult to find.  Once you leave a level, you can never return to it.
Watch out for spells and traps that can suddenly force you off the level.  "Shafts"
are represented by light brown "<" (up) and ">" (down) and will take you up or down 
two levels instead of one.

Secret doors:
     Many secret doors exist in the dungeon, and may lead to anything from a new
section of the dungeon level to an empty closet.  As your familiarity with the
dungeon grows, you will know where many secret doors are likely to be.  Secret
doors always look like granite until found and, for historical reasons, are
never locked.

Traps:
     Traps also await you in the dungeon.  They look like normal floor squares
until found, too often by your being caught by one.
     You find secret doors and traps by using the 's'earch command.  Many
classes can also use magic and everyone can use the appropriate magical device.

Rooms:
     The Pits of Angband contain many kinds of rooms, including some that house
hordes of monsters, contain extraordinary items, or are filled with deadly
traps.  Some special rooms, known as vaults, are extremely dangerous and
lucrative.

Mining:
     There is much treasure in the walls of the dungeon, just waiting for an
industrious adventurer to come and dig it out.  Once you can afford it, and if
you can handle the weight, bring a shovel or pick along.  Your ability to tunnel
depends on strength, weapon weight, and any special digging bonus it provides.
Your success depends on these factors and the strength of the wall:  granite is
very hard, quartz is hard, magma is soft, and rubble is very soft.
     As you get richer, the treasures in the wall won't seem so appealing
anymore, but keep an item or spell of tunneling handy.  Not only do all sorts of
special vaults lie deep below the surface, some completely enclosed by solid
rock, but smart adventurers deliberately alter the dungeon to make the most
dangerous breathers and summoners manageable.


--- Exploring ---

Light:
     Your character must have some source of light in order to see, unless the
area around him is magically lit.  Depending on the items he has equipped, he
may have a light radius of one (a torch), two (a lantern), or more, up to a
rarely-attained maximum of five.  Never risk being without light.
     A torch or lantern burns fuel, and may be refilled (use the 'F'uel command)
with other torches or flasks of oil respectively.  It is rumoured that other
light sources exist which never need replenishing.
     In addition you may get access to spells which permanently light up areas
of the dungeon; these can be truly handy, because a monster you can see coming
is much less dangerous.

Food and Regeneration:
     Never risk being without food.  You must eat every so often in order to
avoid starvation.  The speed at which you consume food depends on your race
(trolls need to eat a lot) and the items you wear.
     The speed at which you regenerate is doubled when you are resting (so rest
in place instead of staying in place whenever possible), and is also affected by
various object attributes and temporary conditions.

Stealth:
     The higher your stealth, and the further away you are, the less you disturb
the rest of sleeping monsters.

Searching and Detection:
     There are two ways to find hidden areas of the dungeon, doors, traps,
objects, and monsters; manual searching and magic.  At the beginning of the
game, you find everything manually.  If you suspect the existence of secret
doors or traps, press 's' to search the grids around you for one turn.  Later
on, you get access to objects and spells that do this for you, and very handy
they are.

Level Feelings:
     If you have spent enough time on the level, you will get a feeling
about that level.  The more interesting the choice of adjectives, the more 
dangerous and lucrative the level is likely to be.
     Things that boost level feelings include:  out of depth monsters, out of
depth uniques, out of depth objects, certain powerful object kinds, very
special rooms, and chests.

Preserve Mode:
     If you do not have preserve mode on, you will occasionally get the message
"You feel there is something special about this level.", indicating the presence
of a monster pit or nest, a vault, or an artifact.
     However, turning preserve mode off also means that artifacts are created
only once; they will never appear again.  You can check the artifacts that have
been found or lost by using the knowledge '~' menu.


--- The Passage of Time ---

     Both monsters and characters gain energy each turn and use it to perform
actions.  Any creature that moves at normal speed gains 10 energy per game turn;
any monster move and most character actions take 100 energy.  Some monsters move
at double speed and you can too, if you quaff a Potion of Speed.  Actions still
take the same amount of energy, but they and you gain twice the energy each
turn.  Further down, monsters lurk that move even faster, and rare items exist
that enable you to keep pace.  If you can, avoid being slower than your foes.

An abbreviated speed-to-energy table:

(very slow creatures can get as little as 1 energy per turn)
     -20 speed:  3 energy
     -15      :  4
     -10      :  5
      -5      :  6
     normal   : 10
      +5      : 15
     +10      : 20
     +15      : 25
     +20      : 30
     +25      : 35
     +30      : 38 (energy only goes up very slowly above +30 speed)

Regeneration and recovery:
     Every 10 game turns, you regenerate some hitpoints and mana (unless you are
ill or wounded), and get hurt by cuts and poison.  Temporary conditions count
down, rods recharge, and light sources use fuel.  Every 100 game turns, you
digest some food.  Every hundred thousand game turns equals one day; the town
spends half that time in darkness and the other half in light.
     Every time it takes a turn, every monster aware of you recovers from
temporary conditions.  Every 100 game turns, they regenerate hitpoints.

