Critical Hits (DMG)

==Critical Hits (Optional Rule)==
Some players feel combat should involve more than just the chance to hit and the amount of damage done. Some propose elaborate tables—critical hit tables—detailing all manner of horrible results and misfortunes.
The simplest critical hit system makes every natural 20 rolled on the attack roll count for double damage. Roll the appropriate damage dice twice for the attack (do not double the result of a single damage roll) and only count damage modifiers for Strength, magic, etc., once.
A second method is to allow characters or monsters to make an extra attack each time they roll a natural 20. The additional attack is made immediately, at the same target, and is figured just like a normal attack. As long as a natural 20 is rolled, the character or monster continues to make additional attacks. A very lucky character could roll a 20 on his first attack and then roll a 20 on his additional attack, allowing him to roll a third attack. If this attack also resulted in a 20, a fourth attack could be made, etc. This system gives characters the chance of causing extra damage without guaranteeing success.
===Critical Fumbles===
Critical fumbles are less easily defined than critical hits. One system that works rules that a die roll of 1 results in some unfortunate event happening to the character who rolled it. The DM must decide what the exact event is based on the situation, although it should not be one that causes damage.
A character could trip and sprawl to the floor, break his sword hitting a stone pillar, get his axe wedged in a wooden beam, or have one of his backpack straps slip off his shoulder, getting in the way. (Of course, magical weapons are not likely to break under normal use.)
The normal result of a critical fumble is the loss of the next round's attack as the character gets up off the floor, digs out a new weapon, pulls his axe out of the beam, or struggles to get his pack where it belongs. Critical failures add a dose of excitement and humor to combat.
Finally, always remember that whatever happens, happens to both player characters and NPCs.