Hacking guide

30 September 1995

PART 6 - HACKING GUIDE

DOOMDARKS REVENGE

Lords of Midnight and its sequel Doomdark's Revenge have been in my top game list ever since I first played them on my old trusty rubber-keyed 48k Spectrum. Even by todays standards, they still rate among the most addictive computer games ever, at least for the strategically minded.

Having played and finished them both several times, I couldn't understand how Mike had been able to stuff so much into only 41k. So I plunged into DR's code... I still have a lot of the original (handwritten) sheets where I deciphered most of the Z80 code for this game. And more important (and useful, probably), the full format of the DR save game, along with some tables which are needed to understand it. Some time ago I posted that on comp.sys.sinclair, and a lot of people was very interested. At least a map editor (by Jan Kapala, email KAPALA@ichn.ch.pwr.wroc.pl) is based in this information, and you can find it in ftp.nvg.unit.no.

Even now I receive some requests for these tables, so here they are... this is the original version I posted then (with some minor corrections, mostly spelling errors) and I don't think there are any mistakes. I hope you find it useful.

DOOMDARKS'S REVENGE MAP AND TABLES

SITES AND CHARACTERS

Example: G Imgarorn: Fortress/Citadel of Imgarorn the Giant. Exceptions noted below.

I = Icelord
G = Giant
D = Dwarf
B = Barbarian
F = Fey
S = Special

All site names are created algorithmically from the map. There's a fixed seed at the upper left corner of the map, and the game traces recursively you position to this point, creating unique names (the name tables will be shown later) for each zone (plains, forest and so on). A citadel or fortress stands as a zone, and it gets its name the same way. There are 128 such sites, and 124 owners. The first 5 sites are special; their owner is not the character with the site name (as in all the others). There are 5 persons which receive special treatment: Luxor the Moonprince, Morkin the Free, Tarithel the Fey, Rorthron the Wise and Shareth the Heartstealer. Shareth owns the City of Imiriel. The other four are foreigners.

This is the full character table:

  0 S Luxor         32 I Berudrarg    64 D Torormarg    96 B Thorthak
  1 S Morkin        33 I Imgudrur     65 I Ushangrane   97 F Thormand
  2 S Tarithel      34 I Talorthane   66 I Fangrorn     98 B Anvorthun
  3 S Rorthron      35 I Morangrim    67 I Carangresh   99 F Imgormand
  4 S Shareth       36 G Obortharg    68 G Anvildrak   100 F Carorthorn
  5 G Imgarorn      37 G Glortheon    69 I Anvarorn   101 B Imgorad
  6 G Ingormad      38 I Ulfangruk    70 D Hagudril   102 F Tororthane
  7 I Malisane      39 I Malarorn     71 G Ganigrorn  103 F Imorthorn
  8 I Anvireon      40 I Ganormarg    72 D Berangrorn 104 F Berormorn
  9 I Talormane     41 G Berorthim    73 G Fenorn     105 B Firak
 10 I Imildrorn     42 I Firim        74 G Sildrorn   106 F Morildrane
 11 I Carorthad     43 I Glireon      75 D Carorthay  107 F Thigrand
 12 I Ushudrarg     44 I Kahangriel   76 B Glortharg  108 B Kahudrarg
 13 G Glormeon      45 I Kahudruk     77 B Thortheon  109 F Lorangriel
 14 G Thormuk       46 I Lororthane   78 D Glormane   110 F Carorthane
 15 I Imgaril       47 I Malirane     79 D Gloruk     111 F Thorthand
 16 G Obularg       48 I Kahudrun     80 D Gludreon   112 F Berormane
 17 I Thigrim       49 G Ulformane    81 D Thudrun    113 F Ingormiel
 18 I Lorelorn      50 D Hagildrorn   82 D Torelorn   114 B Careneon
 19 I Kagangrorn    51 I Thildresh    83 D Thatruk    115 B Varangrand
 20 I Malirarg      52 I Glormarg     84 B Carormand  116 F Imgorthand
 21 G Imatrorn      53 I Carorand     85 D Lorangrarg 117 F Lorangrim
 22 G Asorthane     54 G Carangrane   86 D Thelak     118 F Tharand
 23 I Imasharg      55 G Thangrorn    87 D Imangruk   119 B Torinarg
 24 I Torangrorn    56 I Malormun     88 D Glidril    120 F Imorthesh
 25 I Sortharg      57 I Varormane    89 B Thangrad   121 B Anvortheon
 26 I Zarashand     58 G Imgenarg     90 D Imulorn    122 F Obireon
 27 I Glororn       59 G Thorarg      91 D Thigrak    123 G Obigrorn
 28 I Malorthand    60 I Thirium      92 B Lorangrorn 124 I Imgasharg
 29 G Varangrim     61 I Fenarg       93 B Varatrarg  125 I Thangrarg
 30 I Sigrorn       62 D Imgorarg     94 D Imelorn    126 B Kahudrak
 31 I Hagudrak      63 H Torelak      95 D Ulfangrak  127 F Carorthand

The sites are in North-South order. This may serve as well as a clue to the distribution of the races.

SAVE GAME FORMAT

All the addresses shown from now on are decimal. The saved data starts at Spectrum address 39933, and is 9219 bytes long. This includes:

- Character index                  1
- Day counter                      2
- 24 tables (128 bytes each)    3072
- Map (64*96)                   6144
                                ----
                                9219

Address 39933 holds the number of the character you are using. Addresses 39934-5 hold the number of days 'since the Moonprince rode forth into the Icemark'.

The map and several tables are included here. That's the reason why when you get killed, you must load a saved game to restart (there was no room for two copies of all these data). I will now list all of this. The tables are 128 bytes long, and are indexed by site or character number, as for the above table.

TABLES 0/1 (39936/40064): Site coordinates

Table 0 contains the X coordinates (in the map) for the 128 sites, and table 1 the Y coords. I will not list them as all of you have the map or can get it easily using one of the PD editors.

Each site belongs to the character with the same name. Exceptions:

0 Fortress of Varenand -> Lorangrim the Fey (117)
1 City of Carudrium -> Carorthay the Dwarf (75)
2 Fortress of Thigrorn -> Lorangriel the Fey (109)
3 Fortress of Finorn -> Carangrane the Giant (54)
4 City of Imiriel -> Shareth the Heartstealer

TABLES 2/3 (40192/40320): Object coordinates

As tables 0/1, for objects. Unlike tables 0/1, these are not fixed, and are randomly set at the start of the game. Each object has an owner, who can use it once. Anyone who has an object but is not its owner, won't be able to use it, but will benefit from some minor advantages. They can also be used to approach new people (by giving some object to its true owner you can make him more inclined to join your side).

Objects 5-128 are weapons, their power is in Battle, and belong to the character with the same number. These are Spears (for Barbarians), Bows (for the Fey), Axes (for Dwarves), Hammers (for Giants) and Swords (for Icelords). All of them give advantages in battle.

Objects 0-4 are special. Here are their major powers:

0 Crown of Varenand: Used by Luxor brings all of his men with him.
1 Crown of Carudrium: Used by Morkin brings Luxor and his men.
2 Spell of Thigrorn: Used by Tarithel takes everyone to the city of Imiriel.
3 Runes of Finorn: Used by Rorthron... I don't remember!!!
4 Crown of Imiriel: Used by Shareth brings Luxor and his men.

Crowns have the minor power of Persuasion. They make easier to approach others in peace.

Spells have the minor power of Swiftness (more moves in a day time).

Runes have the minor power of Protection in battle. You are less likely to get killed.

When an object is carried by a character, his number goes on table 3, and table 2 holds 255.

TABLES 4 TO 7

TABLE 4 (40448): Enemies killed in the last battle.
TABLE 5 (40576): Men lost in the last battle.
TABLE 6 (40704): Campaign army size.
TABLE 7 (40832): Home army size (in city or fortress).

All of these tables store the number divided by 5. Thus, 15 means 75 men and 255 (the maximum) means 1275 men.

TABLE 8 (40960): Warrior type (based on table 13)

0-5: Moonguard
6-7: Fey
8-9: Barbarian
10, 11, 14: Iceguard
13: Giant
15: Dwarf

The remaining values are unused.

TABLE 9 (41088): Owner of each site

The initial owners are explained somewhere above. This table holds the actual owners each time.

TABLES 10/11 (41216/41344): Character coordinates

X and Y respectively. Initially, each one is in his home site. Exceptions:

Luxor: Gate of Varenorn.
Morkin: City of Imiriel.
Tarithel: Forest of Fangrim.
Rorthron: Gate of Varenorn.
Shareth: City of Imgaril.

TABLE 12 (41472): Miscellaneous I

a) The 5 upper bits hold the daytime left:

0:     Night
1:     An hour
2-9:   Two hours
10-12: Three hours
13-16: Four hours
17-20: Five hours
21-24: Six hours
25-27: Seven hours
28-30: Eight hours
31:    Dawn

(these days are short!)

b) The 3 lower bits hold the direction of sight:

0: North               2: East
4: South               6: West
1: Northeast           3: Southeast
5: Southwest           7: Northwest

TABLE 13 (41600): Character types

This table is used mainly to select a graphic representation:

 0: Luxor       (mounted)
 1: Luxor       (on foot)
 2: Morkin      (mounted)
 3: Morkin      (on foot)
 4: Rorthron    (mounted)
 5: Rorthron    (on foot)
 6: Fey         (mounted)
 7: Fey         (on foot)
 8: Barbarian   (mounted)
 9: Barbarian   (on foot)
10: Icelord     (mounted)
11: Icelord     (on foot)
12: Tarithel    (always mounted)
13: Giant       (always on foot)
14: Shareth     (always mounted)
15: Dwarf       (always on foot)

There are other codes which are not used in this table, but I include them for completeness. See below for incident codes.

16: Dragon
17: Wolf
18: Troll
19: Skulkrin
20: Horse

TABLE 14 (41728): Miscellaneous II

Bits 0-2: Allegiance
- 0 = Luxor
- 1 = Shareth
- 2 = Fey
- 3 = Barbarians
- 4 = Giants
- 5 = Dwarves
- (6, 7 unused)
Bit 3: Killed enemy in his last battle.
Bit 4: Fought battle (bits 3 and 5 are meaningless if 4 is not set).
Bit 5: Won victory in his last battle.
Bit 6: In a tunnel.
Bit 7: Used his object (only once allowed).

TABLE 15 (41856): How tired

Utterly:    000-031
Extremely:  032-062
Very:       064-095
Quite:      096-127
Somewhat:   128-159
Slightly:   160-191
Not:        192-223
Not at all: 224-255

TABLE 16 (41984): Last battle

In his last battle, this character fought whoever's number is here.

TABLE 17 (42112): Foe

This character's foe. If bit 7 is set, none.

TABLE 18 (42240): Liege

This character's liege. If bit 7 is set, none.

TABLE 19 (42368): How reckless

See table 15. 0 means DEAD.

TABLE 20 (42496): Object/Slayer

This table has two meanings:

a) If alive, then it holds the number of the carried object, or 255 for nothing.
b) If dead, then it holds the number of the character who has killed him. If no character (i.e. dragons, trolls...), then bit 7 is set and the lower bits hold an incident code. See below for incident codes.

TABLE 21 (42624): Positive attributes

Bit Meaning

7   Loyal
6   Swift
5   Brave
4   Stubborn
3   Generous
2   Forceful
1   Strong
0   Good

TABLE 22 (42752): Negative attributes

Bit Meaning

7   Treacherous
6   Slow
5   Cowardly
4   Fawning
3   Greedy
2   Reticent
1   Weak
0   Evil

(...note that it's possible to be simultaneously good and evil!)

TABLE 23 (42880): How despondent

See table 15.

TABLE 24 (43008): MAP (this one is not 128 bytes long!)

The map is 64 squares wide and 96 squares tall. The position at (X,Y) is in address 43008+64*Y+X. Every byte has the following meaning:

Bits 0-3: Surface attributes

   0 Plains       8 Fortress
   1 Mountains    9 Hall
   2 Forest      10 Hut
   3 Hills       11 Tower
   4 Gate        12 City
   5 Temple      13 Fountain
   6 Pit         14 Stones
   7 Palace      15 Frozen Wastes

Bits 4-7: Flags

Bit 4: Incident
Bit 5: Army (only graphical information: you could see an army which isn't really there, or vice versa, by poking this bit!)
Bit 6: Mist.
Bit 7: There's tunnel below. If the surface type is 4-7, there's a tunnel entrance.

So far the saved information. Other tables:

Table 29508: how does terrain (table 24) affect time (table 12a)

Plains:       1
Mountains:    8
Forest:       4
Hills:        3

(All the rest): 2

Table 29540: how does character type (table 13) affect time (table 12a)

(mounted/afoot)

Luxor:      3/6
Morkin:     3/6
Rorthron:   2/4
Fey:        3/6
Barbarians: 5/8
Icelords:   3/5
Tarithel:   2/-
Giants:     -/5
Shareth:    2/-
Dwarves:    -/5

Table 29317: how does character type (table 13) affect tiredness (table 15)

(mounted/afoot)

Luxor:      1/2
Morkin:     2/4
Rorthron:   0/1
Fey:        2/3
Barbarians: 2/4
Icelords:   1/2
Tarithel:   1/0
Giants:     -/2
Shareth:    0/-
Dwarves:    -/3

Table 29009: Four incident types for each possible terrain

(only on empty squares; repeated values increase probability)

Plains:   0,3,1,4    Fortress:  0,1,6,6
Mountains:0,0,2,1    Hall:      2,6,6,10
Forest:   0,3,1,1    Hut:       3,1,6,6
Hills:    0,2,1,1    Tower:     5,5,5,5
Gate:     0,7,8,10   City:      0,6,6,12
Temple:   8,9,10,11  Fountain:  3,12,12,12
Pit:      2,1,9,12   Stones:    0,8,8,11
Palace:   0,4,7,10   Fr. Wastes:0,3,3,2

Incident types:

 0  Dragons
 1  Wolves
 2  Trolls
 3  Skulkrin
 4  Horses
 5  Guidance
 6  Shelter
 7  Claws of Night     (time left =  0)
 8  Flames of Dawn     (time left = 31)
 9  Thorns of Despair  (despondent = 0)
10  Blood of Courage   (despondent = 255)
11  Languor of Death   (tired = 0)
12  Springs of Life    (tired = 255)

NAME TABLES (24839)

All names (except the first five, which are hardcoded) contain three parts, which are fetched more or less randomly (with the map as a seed) by the name generator from three tables. These are:

Prefixes (25):

Img Dol Lor Ush Mor Tal Car Ulf As Tor Ob F Gl S Th Gene Mal Im Var Hag Zar Anv Ber Kah Ash

Midwords (16):

ar or ir en orth angr igr ash el in ul atr orm udr is ildr

Suffixes (16):

orn il iel im uk ium ia eon ay ak arg and esh ad un

The name generator has a fixed seed at position (0,0) of the map. This position holds the fortress of Imgarorn the Giant. As you can see Img-ar-orn is (0,0,0) in the tables above. Any other position is recursively traced down to (0,0), generating a pseudorandom seed for the three tables. The algorithm takes care of any contiguous squares of the same terrain type having the same name.

Note that the map has 6144 positions. 6144=24*16*16, so there is more possible names than squares in the map. So the algorithm also guarantees that there will be no different places with the same name.

That's all for now! Enjoy!

Ruben Martinez
Email: Ruben.Martinez@rediris.es