New House Rule: Roll a 12-Sided Die to Bring Balance to Critical Hits
The critical-hits system currently in use by the official rules of Dungeons and Dragons 4th edition calls for an attacker to obtain a natural 20 on his or her attack die (page 225 PHB) and the roll must also qualify to hit a target’s defense without relying on an automatic hit to hit. So long as these two criteria are met, a critical hit is obtained. This is not a balanced system, though, and here’s why: a poorly skilled fighter, though he doesn’t hit as often as a highly skilled fighter, will, when he does hit, experience a greater percentage of his hits as critical hits. For instance, if the fighter needs a 19 or 20 to hit, the fighter will experience a critical hit with 50% of all hits. Meanwhile, a more skilled fighter who can hit on a 10 or higher will experience a critical hit with one out of ten hits (10% of all hits).
To fix this problem, I propose rolling two dice when attacking instead of one—a 20-sided die and a 12-sided die—and they should both be rolled at the same time.
With this optional rule, an attacker rolls a 12-sided die with the 20-sided die when he or she is attacking, and when the 20-sided die results in a hit, the attacker also checks the 12-sided die. If that die is showing a 12, a critical hit occurs. If any other number is showing, though, no critical hit occurs, and if the 20-sided die does not result in a hit, no critical hit occurs either, even if there is a 12 showing on the 12-die. By contrast, a natural one on the 20-sided die, as stated in the D&D 4th-edition rules, results in an automatic miss and a natural 20 on the 20-sided die still results in an automatic hit, but not a critical hit.
A similar system, if you choose to implement one, can also be put in place to keep track of fumbles (i.e. a miss on the 20-sided die along with a 1 on the 12-sided die results in a fumble, but a 1 on the 12-sided die does not result in a fumble if a hit is achieved with the 20-sided die). Personally, I do not choose to use fumbles because I feel like it is too un-heroic and bitter for my taste and trivial to me, but it can be done.
Once a critical hit is obtained, you can use the normal D&D 4th-edition rules for critical hits (maximum damage plus extra dice for magical or high-crit weapons).
On the other hand, if you so choose, you can instead implement the following house rules and critical-hits tables. If you do, though, note that the charts will, on average, speed up combat and make critical hits even more deadly. You should still add in extra damage dice for magical and high-crit weapons.
(Roll percentile dice)
When a deadly hit occurs, roll % dice on the following chart. If the attacker is the same size or larger than his opponent, either add the attacker’s ability modifier for ST, DEX, INT or WIS (depending on the weapon or spell) to this roll or add the modifier for the difference in size categories that the attacker is larger than his opponent (whichever is highest) as shown on the following chart. By contrast, if the attacker is smaller than his opponent, subtract the appropriate size modifier and adjust the roll by the appropriate ability modifier (add them together).
Once the percentile dice have been modified for the difference in size according to the chart above, compare the final result to the entries on the chart below. And you should still add in extra damage dice for magical and high-crit weapons.
If the spell is a damaging one, all effects are as normal. If it is not a damaging spell, treat the result as a multiplier of how many enemies/people are affected by the spell (double, triple, etc.) or as a multiplier to extend its radius or as a multiplier to affect how long it lasts (whatever makes sense). If no multiplier is apparent on the result obtained from the above chart, treat it as a double multiplier.
[W] or [2W]:
Whenever this term is shown, it represents the highest die normally rolled in that attack if it was not a critical hit. It means you should roll one additional weapon die of that type for [W] or two additional dice of that type for [2W]. For example, if the attack would normally cause 3D10+5 damage a critical hit result of “normal damage + [W] damage” would mean you roll a total of 4D10+5 damage for the hit instead of 3D10+5.
All normal 4th-edition D&D effects (shifts, dazed, knocked prone, etc.) are as outlined in the PHB. Other special effects are outlined below.
Paralyzed, waist down or neck down:
The victim is either permanently paralyzed from the neck down or the waist down (unless magically restored). A successful regenerate body parts ritual will completely heal the wound, so the person no longer suffers any of the above repercussions.
The victim goes to 0 bloody pts and immediately takes normal damage. He must then begin making death saves as outlined in the PHB.
The victim is so obliterated that he or she immediately dies. No saving throws are allowed. Only resurrection will bring him or her back.