From publisher blurb:
There are many players and GMs out there who feel most role playing games are already quite lethal enough without adding insult to injury. This is obviously not the way we feel at Critical Hit Publishing. In fact, adding an additional layer of risk and lethality to combat can not only enhance the overall excitement of the game, but it can encourage role play in several ways. Firstly, role playing is enhanced by compelling players to consider alternatives to combat. After all, when there is a chance that a lowly orc could slice off a character’s hand in combat, they might want to think twice before simply slaughtering their enemy. Secondly, critical hits can often leave scars or even permanent maimings. It is much more interesting to have a character with an eye patch if you know exactly where and how the eye was lost. Such maimings can offer opportunities for characters to develop prejudices, fears, vendettas, and other personality traits that can become pivotal to the story. And thirdly, critical hits can inspire players to create meaningful descriptions of their actions in combat. So rather than simply saying: “I attack with my sword for 6 points of damage,” they might describe the swing, the look on their face or the face of their opponent, and the result. When the players really start to enjoy describing their scenes, even a massive fumble becomes a fun part of the story, and I guarantee that it will be discussed long after the game is over. “Hey, do you remember that time Borek broke his sword fighting that orc chieftain and he ended up killing him with just the pommel!”
Although this was designed to work with many of the popular d20 based fantasy systems, it can easily be adapted for use with almost any system where there is a chance of achieving extraordinary results (good and bad). Naturally, it is impossible to come up with a simple critical chart that will cover any and all possibilities, and so it is expected that the GM or player will adjust the result to be appropriate for the situation. In some cases, certain results may simply not apply. For example, some creatures such as undead and constructs don’t bleed, though they could still suffer a drawback when a limb is removed. Some creatures might not have limbs or bones, but might still bleed. Common sense should always supersede the rules.