I have analysed the famous disarming scene in the film The Maltese Falcon (1941) in GURPS terms, but how does one do it in Call of Cthulhu? I will break down the fight with the rules of Call of Cthulhu, Sixth Edition (and Fifth Edition; earlier editions did not have rules for disarming) and Call of Cthulhu, Seventh Edition.
Watch just the scene here (the action starts at 1:57).
Stop reading if you want to avoid SPOILERS.
Old School
Per Call of Cthulhu, Sixth Edition:
Prelude: Cairo sticks his .25-calibre Colt Vest Pocket pistol (Investigator Weapons 1: The 1920s and 1930s, pp. 43-44) into Spade’s back. As soon as the muzzle makes contact, Spade explodes into action, since now he knows exactly where the pistol and Cairo’s hand are.
1st Combat Round: Spade initiates a Surprise Attack (Call of Cthulhu, Sixth Edition, p. 56). The Keeper decides that Cairo is extremely surprised and thus cannot attack this combat round. Spade makes a Grapple roll, which succeeds, and Cairo fails his Dodge roll to evade. Cairo is now grappled; Spade selects the option to Injure (Call of Cthulhu, Sixth Edition, p. 68) and makes a second Grapple roll, which succeeds. Cairo takes 1D6+db damage. The inflicted damage seems excessive. The reason for this is that the Injure option under Grapple assumes that the damage comes from a grappling hold such as an arm lock or chokehold. Spade, however, actually strikes. The Keeper house-rules that Spade has to make the second roll against Fist/Punch, which brings the damage down to 1D3+db. The Keeper decides that Cairo is stunned for 1D6 combat rounds (Call of Cthulhu, Sixth Edition, p. 54).
2nd Combat Round: Spade has Cairo grappled and makes a Grapple roll to Disarm Cairo (Call of Cthulhu, Sixth Edition, p. 68). The roll succeeds and Cairo fails his Grapple roll to parry. The pistol falls to the ground. Cairo is still stunned and cannot attack.
3rd Combat Round: Spade has Cairo grappled and makes a Fist/Punch roll to Injure Cairo (see above). The roll succeeds and Cairo fails his Dodge roll. Cairo takes another 1D3+db damage. Cairo is still stunned and cannot attack.
4th Combat Round: Spade has Cairo grappled and makes a Fist/Punch roll to Knock Out Cairo (Call of Cthulhu, Sixth Edition, pp. 68, 60). Ordinarily, this roll would have to be against Grapple again, as it is intended to mimic a chokehold or similar, but the Keeper house-rules again that Fist/Punch is an acceptable substitute. The roll succeeds and Cairo fails his Dodge roll. Spade matches 1D3+db damage against Cairo’s Hit Points on the Resistance Table (Call of Cthulhu, Sixth Edition, p. 55). He probably rolls a Critical Success for doubled damage (Call of Cthulhu, Sixth Edition, p. 140) in order for this to work. Either way, Cairo takes 1/3 of the rolled damage as actual damage and falls unconscious.
New School
Per Call of Cthulhu, Seventh Edition:
Prelude: Cairo sticks his .25-calibre Colt Vest Pocket pistol into Spade’s back. As soon as the muzzle makes contact, Spade explodes into action, since now he knows exactly where the pistol and Cairo’s hand are.
1st Combat Round: Spade strikes the first blow (Call of Cthulhu, Seventh Edition, p. 106). Cairo is completely surprised and Spade gets a bonus die this combat round (Call of Cthulhu, Seventh Edition, p. 107). Spade takes a Disadvantage manoeuvre (Call of Cthulhu, Seventh Edition, p. 106) to restrain Cairo’s right arm holding the pistol. Spade has the higher Build and therefore suffers no penalty die on the manoeuvre (Call of Cthulhu, Seventh Edition, pp. 105-106). Spade and Cairo make an opposed roll between Fighting (Brawl) and Dodge, Spade with one bonus die. Spade has the higher success; he is now holding Cairo’s arm and Cairo suffers one penalty die on his actions until he is released (Call of Cthulhu, Seventh Edition, p. 106). Cairo does nothing, being surprised.
2nd Combat Round: Spade attacks Cairo by hitting him with the left hand while holding Cairo’s right. Spade and Cairo make an opposed roll between Fighting (Brawl) and Dodge, Cairo with one penalty die. Spade has the higher success and does 1D3+db damage to Cairo. Cairo does nothing.
3rd Combat Round: Spade performs a Disarm manoeuvre (Call of Cthulhu, Seventh Edition, p. 106). Spade and Cairo make an opposed roll between Fighting (Brawl) and Dodge, Cairo with one penalty die. Spade has the higher success and Cairo is disarmed; the pistol falls to the ground. Cairo does nothing.
4th Combat Round: Spade attacks Cairo by hitting him again with the left hand while holding Cairo’s right. Spade and Cairo make an opposed roll between Fighting (Brawl) and Dodge, Cairo with one penalty die. Spade has the higher success and does 1D3+db damage to Cairo. Cairo does nothing.
5th Combat Round: Spade performs a Knock-Out manoeuvre (Call of Cthulhu, Seventh Edition, p. 125) by punching Cairo on the chin. Spade and Cairo make an opposed roll between Fighting (Brawl) and Dodge, Cairo with one penalty die. Spade has the higher success; Cairo takes 1 point of damage and falls unconscious.
Results
Call of Cthulhu, Sixth Edition, suffers from the terrible definition of its combat round, which is “several [more than two] to a dozen or so seconds long” (Call of Cthulhu, Sixth Edition, p. 56). In other words, while the entire engagement takes less than 8 seconds of screen time including a lingering close-up on the dropped pistol, the four combat rounds required to actually model the action in the game add up to 12-48 seconds. I usually suggest to use a fixed 3-second combat round (Investigator Weapons 1, p. 30, and Investigator Weapons 2, pp. 49-50), but even that is long in comparison to this scene.
In the game, Spade would probably strike Cairo only once before disarming and then knocking him out, although that scene is more about style than anything; it is pure machismo. To solve situations like this, some Keepers interpret any unarmed attack with Fist/Punch, Grapple, Head Butt, or Kick as an actual combination of several individual strikes, although the descriptions of the skills do not support this and it would make the back-and-forth between attack and parry pointless.
The combat round in Call of Cthulhu, Seventh Edition, is less problematic, being defined to be as long as required for every character to perform one action (Call of Cthulhu, Seventh Edition, p. 102). Representing a combat round’s worth of the back-and-forth of attacks and parries as a single opposed roll is in many ways a useful abstraction, but becomes less realistic as soon as the characters try to do more specific manoeuvres. The reduction of damage for unarmed attacks improves the overall suspension of disbelief considerably. Combining the old unarmed skills streamlines the whole fight. Unfortunately, the rules no longer allow someone to be stunned ‒ unless hit with a stun weapon (Call of Cthulhu, Seventh Edition, p. 406). This is not only unrealistic but also means that Cairo inexplicably just stands there while being abused by Spade. While this is probably rather realistic behaviour for people unaccustomed to violence, there is no game-mechanical reason for it.
In both editions, the Keeper has to fill in the holes in the rules system to arrive at a coherent picture. As long as that is understood by both the Keeper and the players, this works fine. However, the rules-light approach requires more insight in how this actually works in real-life, at least if a realistic result is intended.
Shooting Dice 