When an attacker scores and confirms a critical hit, instead of doubling the damage, maximum weapon damage is done. Additionally, roll 3d6 and consult the following table. If the weapon is a x3 weapon, roll twice; if the weapon is a x4, roll three times.
|3||Roll damage dice again. Do not add extra damage. Roll on this table again, ignoring a roll of 3 or 18.|
|4||Blow to face. Target takes 1d3 CHA damage and is blinded until he spends a standard action to clear the blood from his eyes.|
|5||Blow to chest. Target has wind knocked out and is dazed for 1 round.|
|6||Blow to legs. Make a free trip attempt, and target’s move is reduced by 1/2 for 1d6 rounds.|
|7||Blow to limb. Make a free disarm attempt if applicable, and target cannot use one weapon or attack for 1d6 rounds.|
|8 – 10||Roll damage dice again. Do not add any extra damage from STR, Power Attack, etc.|
|11 – 13||Roll damage dice again. Add extra damage from STR, Power Attack, etc.|
|14||Blow to gut. Target loses next action and is sickened for 1d6 rounds.|
|15||Blow to throat. Target cannot speak, eat or drink for 1d6 rounds, rendering spellcasting and item completion impossible.|
|16||Blow to head. Target stunned for 1 round.|
|17||Bleeding wound. Roll damage dice again; this much damage is dealt each round on your turn. Fort save or healing ends (DC 10 + ongoing damage amount).|
|18||Roll damage dice again. Add extra damage from STR, Power Attack, etc. Roll on this table again, ignoring a roll of 18.|
It should be noted that some common sense should be applied to these results. If, for example, a creature has multiple heads, rolling a 16 will not likely have much effect.
Where possible, these effects should be adapted in order to thematically approximate the mechanical effect. Thus, even though fish do not have legs (for example), a blow to their tail would still result in reducing their movement by half, and thus a result of 6 on the table can still be applied. If a result is rolled that is simply not applicable (such as a throat strike on a creature without a throat), ignore the result and reroll.
Definition of extra damage: damage from STR bonus, power attack, weapon enhancement bonuses, class features that add a fixed amount of damage (e.g. a ranger's favored enemy bonus or a paladin's smite evil), and other fixed damage bonuses. Sneak attack (and variants thereof) and additional weapon damage dice (such as from the flaming ability) are not rolled again. (See PHB page 140 and the SRD pages for Rogue and Magic Weapons.)