TEXT: A critical miss is a natural 1 attack roll that might result in the attacker suffering something untoward. 
  Such a “fumble” can occur at the most inopportune moments; blunders that can lead to embarrass-
  ment, defeat, or death. Like critical hits, critical misses infuse the game with greater danger and thus 
  greater tension. Note that if a result does not suit the situation, the referee is instructed to shift to the 
  preceding result. For example, if a monk is attacking with his fists and the critical miss result is “drop 
  weapon”, simply select the “bad miss” result.
  XATHOQQUA’S WOE
  Critical Misses (Optional) for Hyperborea™
  d12 Roll
  Combatant Type
  Fighter
  Cleric, Thief, Monster
  Magician
  1
  bad miss
  bad miss
  bad miss
  2
  bad miss
  bad miss
  bad miss
  3
  bad miss
  bad miss
  drop weapon
  4
  bad miss
  bad miss
  drop weapon
  5
  bad miss
  drop weapon
  stumble
  6
  bad miss
  drop weapon
  stumble
  7
  drop weapon
  stumble
  trip/fall
  8
  drop weapon
  stumble
  trip/fall
  9
  stumble
  trip/fall
  hit ally
  10
  trip/fall
  trip/fall
  hit ally
  11
  hit ally 
  hit ally
  hit self
  12
  hit self
  hit self
  hit self
  Bad Miss: An embarrassing attack attempt, worthy of ridicule; attack routine may continue.
  Drop Weapon: Weapon pitches 1d6+4 feet in random direction (d6, 1–3 = forward, 4 = left, 5 = right,  
  6 = backward). A wall or other obstacle may limit the distance a weapon propels.
  Stumble: Awkward stumble. One adjacent enemy (if applicable) gets one free attack. No further  
  attacks possible for the rest of the round, if applicable.
  Trip/Fall: Prone (–4 AC, no shield bonus, no DX bonus) for remainder of round and until next available 
  action (i.e., status of being prone in the next round is initiative dependent).
  Hit Ally: Complete blunder results in closest (melee) or closest to intended target (missile) ally being 
  struck for normal damage. No further attacks possible for the rest of the round, if applicable.
  	
  ♦
  If combatant type is fighter, 1-in-8 chance to inflict critical damage to ally. 
  	
  ♦
  If combatant type is cleric, thief, monster, 2-in-8 chance to inflict critical damage to ally. 
  	
  ♦
  If combatant type is magician, 3-in-8 chance to inflict critical damage to ally.
  Hit Self: Complete attack mishap results in normal damage inflicted to self. No further attacks  
  possible for the rest of the round, if applicable.
  	
  ♦
  If combatant type is fighter, 1-in-8 chance to inflict critical damage to self. 
  	
  ♦
  If combatant type is cleric, thief, monster, 2-in-8 chance to inflict critical damage to self. 
  	
  ♦
  If combatant type is magician, 3-in-8 chance to inflict critical damage to self.
  NB (1): Refer to Table 98 of AS&SH Vol. III for all critical damage results.
  NB (2): Some intelligent, weapon-wielding monsters (lizard-men, orcs, snake-men, etc.) may use the 
  fighter column or the magician column, per referee discretion.
  © 2020 North Wind Adventures, LLC
  
SOURCE: textdata/thevault/Astonishing Swordsmen and Sorcerers of Hyperborea/AS&SH Supplemental/AS&SH Xathoqqua's Woe (Critical Misses).pdf