Hello all!
Still reading the rules book, but not in the combats section yet, if I understood well with all I've read so far the critics applied in a combat are just a matter of multiplying the hit damages. That'd be fine, but I remember that 20 years ago, when I was playing LOTR, we had in that game a "critics table" far more fun to play: depending of the critics dies roll, and the type of weapon used, the results were different. For example, a natural 20 resulted in a head cut (in case of a cutting weapon), a head smatched (in case of a blunt weapon),...Lesser die result leaded to a hand or a leg cut, for example, with HP loss and also some other negative points.
Does such a table exist for PathFinder? Else I'll probably try to create one myself.
There is no official tables, in the core rules, that I am aware of for critical hits or critical fumbles. Most people (that use them) either make their own or use a third party's tables.
There are Critical Hit and Critical Fumble card decks available, but they're...interesting.
Basically, if you crit, you draw a card from the deck. The card contains extra information that you then apply, damage- or stat-wise to your critical hit or fumble. Things like you said: Decapatations, limb cuts, eye pokes, groin shots, etc.
It's all fun and games until you cut your own head off with a critical fumble.
Stop looking at me like that. It wasn't my character that did that.
There is Torn Asunder: Critical Hits by Dragon Wing Games
I use the critical hit and critical fumble decks,
there is also the critical hit table in the Dragon Compendium.
Thank you all! Meanwhile I followed the advice of Rite Publishing: I bought Torn Asunder's criticals hits rules book, and indeed it seems veeeery complete (more than 150 pages ^^)!