TEXT: Multi-Classing for Castles and Crusades
  By Erac’s Cousin’s Uncle (Al Krombach)
  This  optional  multi-classing  system  was 
  designed with this in mind: “Keeping it Simple”. 
  It was inspired by the original Fighter/Magic-
  User class found in the Basic Dungeons and 
  Dragons rulebook: the “Elf.”
  I  advise  you  to  only  allow  the  four  “base” 
  classes (Fighter, Cleric, Rogue, and Wizard) to 
  be multi-classable, as other classes are more 
  specialized and focused, and therefore much 
  harder  to  effectively  employ  while  dividing 
  time  with  another  class.  Three  notable 
  exceptions  I  include  here  (mainly  for  1E 
  nostalgia  purposes)  are  the  Gnome  Rogue-
  Illusionist,  the  Half-elf  Ranger-Druid,  and  the 
  Half-orc Cleric-Assassin. That’s just my opinion, 
  though, and if you feel your campaign needs 
  Barbarian-Monks, this system is just as easy to 
  use for stuff like that, too.
  Race: I’ve  listed  suggested  races  for  each 
  multi-class,  but  this  is  based  more  on  1E 
  sensibilities (or literary examples) than on any 
  practical  reason.  It  could  be  argued  that 
  humans aren’t long-lived enough to train in 
  two  classes,  and  that  dwarves  aren’t 
  inherently  magical  enough  to  train  in  spell-
  using classes, but this is really dependent on 
  your  own  campaign,  so  use  your  best 
  discretion. For example, I listed human among 
  the  races  for  Fighter-Rogues,  for  the 
  Swashbuckler/Musketeer-type characters, and 
  with  the  Cleric-Wizard,  for  the  stereotypical 
  “Master of White Magic”.
  Prime Attribute: The multi-class uses the Prime 
  Attributes  from  both  base  classes,  and  the 
  player must select them both. This can reduce 
  the  flexibility  of  the  character,  but  it  is  a 
  necessary  sacrifice  for  the  advantages  of 
  multi-classing. If three classes are multi-classed, 
  and  the  character  is  non-human  (receiving 
  only 2 primes), the CK must rule whether the 
  character must sacrifice the additional prime, 
  or just award it to the player as a “bonus” to 
  compensate for the resulting lag in levels.
  Hit Dice: Figure the multi-class’s Hit Dice per 
  level by adding the max result of each base 
  class’s Hit Dice together and dividing by 2 (or 
  3,  in  triple-multi-class  situations),  and  then 
  apply  the  die  type  most  appropriate.  For 
  instance,  a  Fighter  (d10,  or  10  max)  and 
  Wizard (d4, or 4max) yields a result of 7 max hit 
  points per level. Therefore, the Hit Die assigned 
  would be d6+1. If necessary, round down. For 
  hit points gained after 10th level, add the base 
  class hit points and divide by two (or more). 
  Round down if necessary. 
  BtH: Use  the  best  BtH  available  from  either 
  class. For instance, a Fighter-Rogue would use 
  the Fighter’s BtH progression, not the Rogue’s.
  EPP: The multi-class uses the sum total of both 
  base  classes  to  determine  the  experience 
  necessary to gain each level. For instance, a 
  Fighter  (2,001) and Rogue (1,251)  multi-class 
  must gain a total of 3,252 exp before leveling. 
  All  level-related  increases  are  gained  ONLY 
  upon attaining the FULL required experience 
  point total.
  Alignment: The  multi-class  character  must 
  abide  by  the  alignment  restrictions  of  both 
  classes.  Classes  with  conflicting  alignment 
  requirements (say, Druid and Paladin), should 
  NOT be multi-classed.
  Armor: Use  the  most  favorable  class  to 
  determine  allowable  armors,  but  allow  for 
  common-sense  restrictions  according  to  the 
  base classes. For instance, multi-classes based 
  on  Rogue,  Monk,  or  Druid  will  have  some 
  obvious  restrictions.  I  do  not  impose  armor 
  restrictions on multi-classed arcane spell users 
  (another nod to 1E), as this stems mainly from 
  a 2E “nerfing” of Fighter-Magic Users, rather 
  than  from  any  actual  literary  or  legendary 
  examples.  Personally,  I  feel  somatic 
  components to be hand-gestures rather than 
  intricate  interpretive  dance,  so  I  do  restrict 
  shield use to keep a hand free, but impose no 
  further restrictions. I have found that low-level 
  characters can’t afford really good armor and 
  high level characters choose between magic 
  chainmail  and  +8  bracers  on  a  largely 
  cosmetic  basis.  Single-classed  wizards  and 
  illusionists don’t use armor for the same two 
  reasons they don’t use greatswords: they have 
  neither the training nor the interest to do so. If, 
  however, it just seems WRONG to you, feel free 
  to  disallow  armor  use  to  the  arcane  multi-
  classes in your campaign.
  Page 1
  
  Weapons: As with armor, use the base class 
  with  the  best  selection  and  make  any 
  common-sense restrictions necessary.
  Abilities: The  multi-class  gains  all  abilities  of 
  each base class, at the same level as the base 
  class. In the interest of “keeping things simple” 
  avoid the urge to rule-combine class abilities in 
  any  way.  While  I’m  sure  there  are  some 
  interesting ways to mix druidic shapechanging 
  with assassin death attacks, or whatever, you 
  are  probably  better  off  not  opening  any 
  unnecessary doors of exploitation.
  Multi-class Tables: For your convenience, the 
  most  common  multi-classes  are  detailed  on 
  the  following  pages,  with  all  the  number-
  crunching done for you already. If you want 
  some other combos, you’re on your own, but it 
  really doesn’t take long to do. Included here 
  are the following multi-classes: Fighter-Wizard, 
  Fighter-Rogue, Rogue-Illusionist, Fighter-Rogue-
  Wizard,  Fighter-Cleric,  Rogue-Cleric,  Rogue-
  Wizard,  Ranger-Druid,  Cleric-Assassin,  and 
  Cleric-Wizard.
  Fighter/Wizard
  (Elf, Half-elf)
  Prime Attributes: Strength and Intelligence
  Alignment: Any
  Hit Dice: d6+1
  Weapons: Any
  Armor: Any (no shields)
  Abilities: As per Core Classes
  Level
  HD
  BtH
  EPP
  Level/Spells per day
  1
  d6+1
  +1
  0
  4/2
  2
  d6+1
  +2
  4,602
  4/3
  3
  d6+1
  +3
  9,202
  4/3/1
  4
  d6+1
  +4
  18,902
  4/3/2
  5
  d6+1
  +5
  37,802
  5/4/2/1
  6
  d6+1
  +6
  76,502
  5/4/3/2
  7
  d6+1
  +7
  153,002
  5/4/3/2/1
  8
  d6+1
  +8
  306,002
  5/4/3/3/2
  9
  d6+1
  +9
  612,002
  5/5/4/3/2/1
  10
  d6+1
  +10
  1,000,002
  6/5/4/3/3/2
  11
  +2hp
  +11
  1,500,002
  6/5/4/4/3/2/1
  12
  +2hp
  +12
  2,000,002
  6/5/4/4/3/3/2
  13+
  500,000 per level
  Page 2
  
  Fighter/Rogue
  (Half-elf, Human, Halfling, Half-orc)
  Prime Attributes: Strength and Dexterity
  Alignment: Any
  Weapons: Any
  Armor: As Rogue
  Abilities: As per Core Classes
  Level
  HD
  BtH
  EPP
  1
  d8
  +1
  0
  2
  d8
  +2
  3,252
  3
  d8
  +3
  6,502
  4
  d8
  +4
  14,502
  5
  d8
  +5
  29,002
  6
  d8
  +6
  58,002
  7
  d8
  +7
  116,002
  8
  d8
  +8
  216,002
  9
  d8
  +9
  392,002
  10
  d8
  +10
  675,002
  11
  +3hp
  +11
  1,075,002
  12
  +3hp
  +12
  1,450,002
  13+
  375,000 per level
  Rogue/Illusionist
  (Gnome)
  Prime Attributes: Dexterity and Intelligence
  Hit Die: d4+1
  Alignment: Any Chaotic
  Weapons: As Rogue
  Armor: As Rogue (no shields)
  Abilities: As per Core Classes
  Level
  HD
  BtH
  EPP
  1
  d4+1
  +0
  0
  2
  d4+1
  +1
  3,852
  3
  d4+1
  +1
  7,702
  4
  d4+1
  +1
  16,402
  5
  d4+1
  +2
  32,802
  6
  d4+1
  +2
  66,502
  7
  d4+1
  +2
  133,002
  8
  d4+1
  +3
  250,002
  9
  d4+1
  +3
  460,002
  10
  d4+1
  +4
  675,002
  11
  +1hp
  +4
  1,075,002
  12
  +1hp
  +4
  1,350,002
  13+
  275,000 per level
  Fighter/Rogue/Wizard
  (Elf and Half-elf)
  Prime Attributes: Choose 2: Strength, Dexterity, or Intelligence
  Hit Die: d6
  Alignment: Any
  Weapons: Any
  Armor: As Rogue (no shields)
  Abilities: As per Core Classes
  Level
  HD
  BtH
  EPP
  Level/Spells per day
  1
  d6
  +1
  0
  4/2
  2
  d6
  +2
  5,801
  4/3
  3
  d6
  +3
  11,502
  4/3/1
  4
  d6
  +4
  24,902
  4/3/2
  5
  d6
  +5
  49,802
  5/4/2/1
  6
  d6
  +6
  100,502
  5/4/3/2
  7
  d6
  +7
  201,002
  5/4/3/2/1
  8
  d6
  +8
  386,002
  5/4/3/3/2
  9
  d6
  +9
  732,002
  5/5/4/3/2/1
  10
  d6
  +10
  1,175,002
  6/5/4/3/3/2
  11
  +3hp
  +11
  1,825,002
  6/5/4/4/3/2/1
  12
  +3hp
  +12
  2,450,002
  6/5/4/4/3/3/2
  13+
  625,000 per level
  Page 3
  
  Fighter-Cleric (Dwarf, Half-elf, Human):
  Prime Attributes: Strength and Wisdom
  Hit Die: d8+1
  Alignment: Any
  Weapons: Any
  Armor: Any
  Abilities: As per Core Classes
  Level
  HD
  BtH
  EPP
  Level/Spells per day
  1
  d8+1
  +1
  0
  3/1
  2
  d8+1
  +2
  4,252
  4/2
  3
  d8+1
  +3
  9,002
  4/2/1
  4
  d8+1
  +4
  17,502
  4/3/2
  5
  d8+1
  +5
  35,002
  4/3/2/1
  6
  d8+1
  +6
  79,002 
  5/3/3/2
  7
  d8+1
  +7
  138,002
  5/4/3/2/1
  8
  d8+1
  +8
  276,002
  5/4/3/3/2
  9
  d8+1
  +9
  572,002
  5/4/4/3/2/1
  10
  d8+1
  +10
  925,002
  5/4/4/3/3/2
  11
  +3hp
  +11
  1,400,002
  6/5/4/4/3/2/1
  12
  +3hp
  +12
  1,900,002
  6/5/4/4/3/3/2
  13+
  500,000 per level
  Rogue-Cleric (Half-elf, Half-orc, Halfling)
  Prime Attributes: Dexterity and Wisdom
  Hit Die: d6+1
  Alignment: Any
  Weapons: As per Core Classes
  Armor: As per Rogue
  Abilities: As per Core Classes
  Level
  HD
  BtH
  EPP
  Level/Spells per day
  1
  d6+1
  +0
  0
  3/1
  2
  d6+1
  +1
  3,502
  4/2
  3
  d6+1
  +1
  7,502
  4/2/1
  4
  d6+1
  +2
  15,002
  4/3/2
  5
  d6+1
  +2
  30,002
  4/3/2/1
  6
  d6+1
  +3
  59,002
  5/3/3/2
  7
  d6+1
  +3
  118,002
  5/4/3/2/1
  8
  d6+1
  +4
  220,002
  5/4/3/3/2
  9
  d6+1
  +4
  420,002
  5/4/4/3/2/1
  10
  d6+1
  +5
  600,002
  5/4/4/3/3/2
  11
  +2hp
  +5
  775,002
  6/5/4/4/3/2/1
  12
  +2hp
  +6
  1,350,002
  6/5/4/4/3/3/2
  13+
  375,000 per level
  Page 4
  
  Rogue-Wizard (Elf, Half-elf)
  Prime Attributes: Dexterity and Intelligence
  Hit Die: d4+1
  Alignment: Any
  Weapons: As per Core Classes
  Armor: As per Rogue (no shields)
  Abilities: As per Core Classes
  Level
  HD
  BtH
  EPP
  Level/Spells per day
  1
  d4+1
  +0
  0
  4/2
  2
  d4+1
  +1
  3,852
  4/3
  3
  d4+1
  +1
  7,702
  4/3/1
  4
  d4+1
  +1
  16,402
  4/3/2
  5
  d4+1
  +2
  32,802
  5/4/2/1
  6
  d4+1
  +2
  66,502
  5/4/3/2
  7
  d4+1
  +2
  133,002
  5/4/3/2/1
  8
  d4+1
  +3
  250,002
  5/4/3/3/2
  9
  d4+1
  +3
  460,002
  5/5/4/3/2/1
  10
  d4+1
  +3
  675,002
  6/5/4/3/3/2
  11
  +1hp
  +4
  1,075,002
  6/5/4/4/3/2/1
  12
  +1hp
  +4
  1,450,002
  6/5/4/4/3/3/2
  13+
  375,000 per level
  Ranger-Druid (Half-elf)
  Prime Attributes: Strength and Wisdom
  Hit Die: d8+1
  Alignment: Neutral (any)
  Weapons: Any
  Armor: As per Druid
  Abilties: As per Core Classes
  Level
  HD
  BtH
  EPP
  Level/Spells per day
  1
  d8+1
  +0
  0
  3/1
  2
  d8+1
  +1
  4,252
  4/2
  3
  d8+1
  +2
  8,752
  4/2/1
  4
  d8+1
  +3
  17,502
  4/3/2
  5
  d8+1
  +4
  35,002
  4/3/2/1
  6
  d8+1
  +5
  75,002
  5/3/3/2
  7
  d8+1
  +6
  145,002
  5/4/3/2/1
  8
  d8+1
  +7
  330,002
  5/4/3/3/2
  9
  d8+1
  +8
  525,002
  5/4/4/3/2/1
  10
  d8+1
  +9
  900,002
  5/4/4/3/3/2
  11
  +3hp
  +10
  1,250,002
  6/5/4/4/3/2/1
  12
  +3hp
  +11
  1,600,002
  6/5/4/4/3/3/2
  13+
  400,000 per level
  Page 5
  
  Cleric-Assassin (Half-orc)
  Prime Attributes: Wisdom and Dexterity
  Hit Dice: d6+1
  Alignment: Any non-good
  Weapons: Any
  Armor: As per Assassin
  Abilitities: As per Core Classes
  Level
  HD
  BtH
  EPP
  Level/Spells per day
  1
  d6+1
  0
  0
  3/1
  2
  d6+1
  +1
  4,002
  4/2
  3
  d6+1
  +1
  8,502
  4/2/1
  4
  d6+1
  +2
  16,002
  4/3/2
  5
  d6+1
  +2
  32,002
  4/3/2/1
  6
  d6+1
  +3
  60,002
  5/3/3/2
  7
  d6+1
  +3
  120,002
  5/4/3/2/1
  8
  d6+1
  +4
  230,002
  5/4/3/3/2
  9
  d6+1
  +4
  450,002
  5/4/4/3/2/1
  10
  d6+1
  +5
  625,002
  5/4/4/3/3/2
  11
  +2hp
  +5
  1,000,002
  6/5/4/4/3/2/1
  12
  +2hp
  +6
  1,400,002
  6/5/4/4/3/3/2
  13+
  400,000 per level
  Cleric-Wizard (Half-elf, Human)
  Prime Attributes: Wisdom and Intelligence
  Hit Dice: d6
  Alignment: Any
  Weapons: As per Cleric plus dart.
  Armor: Any (no shields)
  Abilities: As per Core Classes
  Level
  HD
  BtH
  EPP
  Level/Spells (Cleric)
  Level/Spells (Wizard)
  1
  d6
  0
  0
  3/1
  4/2
  2
  d6
  +1
  4,852
  4/2
  4/3
  3
  d6
  +1
  10,202
  4/2/1
  4/3/1
  4
  d6
  +2
  19,402
  4/3/2
  4/3/2
  5
  d6
  +2
  38,802
  4/3/2/1
  5/4/2/1
  6
  d6
  +3
  77,502
  5/3/3/2
  5/4/3/2
  7
  d6
  +3
  155,002
  5/4/3/2/1
  5/4/3/2/1
  8
  d6
  +4
  310,002
  5/4/3/3/2
  5/4/3/3/2
  9
  d6
  +4
  640,002
  5/4/4/3/2/1
  5/5/4/3/2/1
  10
  d6
  +5
  925,002
  5/4/4/3/3/2
  6/5/4/3/3/2
  11
  +2hp
  +5
  1,400,002
  6/5/4/4/3/2/1
  6/5/4/4/3/2/1
  12
  +2hp
  +6
  1,900,002
  6/5/4/4/3/3/2
  6/5/4/4/3/3/2
  13+
  500,000 per level
  Legalities: This document requires the use of the Castles and Crusades Players Handbook, is 
  Open Game Content, and is strictly for free. If you don’t know what the OGL is, please visit 
  http://www.wizards.com/default.asp?x=d20/welcome to learn more.
  Page 6
  
SOURCE: textdata/thevault/Castles & Crusades Siege Engine/Castles & Crusades Classes/Castles & Crusades Multi-Classing.pdf