The Armor Class Equalizer

Sometimes the best weapons to use against armored opponents are not those that inflict the most damage, but those that deprive them of the advantage of wearing armor. Armor is best for deflecting or absorbing attacks, but it is the worst for avoiding attacks. The mounted knight or man-at-arms is particularly vulnerable to the hooked pole arms used by footmen and peasantry to pull them off their steeds.

This is a simple rule that can be added to any role-playing game that utilizes armor class in combat resolution.

Any attacker who uses an appropriate weapon with the intent of pulling, pushing, toppling, entangling, or unhorsing an opponent may consider that opponent to be unarmored in terms of armor class regardless of whatever armor that opponent may be wearing. If the opponent is aware of the attack and able to react, the opponent's armor class will be modified by his or her Dexterity bonus or penalty, if any. Appropriate weapons include whips, bolas, man-catchers, and most pole arms (namely those with hooks and/or tines). If the attack is successful, it causes no damage, but the victim is affected as follows:

• whip: entangled (potentially tripped or disarmed)
  
• bola: entangled (potentially tripped)
  
• man-catcher: caught (potentially pushed or pulled)
  
• pole arm: unhorsed or tripped
  

Effects may be adjudicated by GM fiat, GM-player negotiation, attribute checks, or any extant rules covered by the system being used.