I finally had the chance (and the money) to pick up the Game Mastery Critical Hit Deck put out by Paizo Publishing. I’d heard about it a few months ago, and it was an Ennie Awards nominee in 2006, so clearly I’m late to the game, but regardless I think it was a good buy.
It actually does something similar to what HARP/Rolemaster tries to do with its critical damage tables – to make damage dealt in combat feel unique, and not just another chunk out of an opponent’s hit points or whatever measure you’re using.
Basically, when a critical hit is “confirmed” (a’la the D20 rules), you draw a card from the deck. One each card are four descriptions of different effects that a critical hit might entail – for Bludgeoning, Piercing, Slashing and Magical attacks. Each gives you a special effect of some kind that is far more colorful than simply double damage. Examples include dealing double damage and switching places with your target (Magical), battering someone so they have memory loss (Bludgeoning), jamming your weapon in an opponent’s mouth (Piercing) and permanently blinding an opponent (Ref negates).
I think this would work well in a cinematic game where only PCs get to use the deck, and also for a grittier game where NPCs and monsters can also use it, upping the threat ante in any encounter. Its also probably adaptible to other systems that have a critical hit function of some kind that you want to spice up. You can easily ignore the little notes about D20 effects of each blow and just translate them into the system you’re using.
Overall, I’m not sure how to rate this one, but I’ll give it a 4.5 out of 5, because it does exactly what it is supposed to do in a fun and simple way, but it would be perfect if it was a bit more accommodating to use with other systems.