Maximum Damage

We've been playing with a lot of ideas using D&D weapons and margins of success. Yesterday, a new one occurred to me: maximum damage.

Let's say weapon damage is determined by margin of success, but the maximum damage is unchanged from the original game. So a d4 becomes 4, a d8 becomes 8, etc.

This has several benefits before we get any deeper:

• You don't need a damage roll.
• Damage raises steadily with level, especially for fighters.
• Armor becomes even more significant.
• Armored duels
•  feel a bit slower and more realistic, with lots of wounds.
• Magic users could use swords etc. but it would usually not be worth the effort.
• We'd get more granular weapons (e.g., maximum damage 5, 7, or 9).
• Even a goblin can potentially survive a hit of a +3 sword, although this is very rare.

If we rule that a natural 20 doubles or triples maximum damage (or just raises it by 10 points or whatever), even a dagger can be deadly in the hands of a very skilled fighter against an unarmored foe.

Conversely, we can introduce laser guns with 15 or 20 maximum damage, and he stormtroopers would still have a hard time actually killing someone with it in a single shot.

I'm tempted to add your attack bonus to maximum damage too, so Conan can occasionally kill a sorcerer with a punch.

We'd have to consider how backstab works. Maybe a flat +4 bonus to attack and maximum damage.

Also, how do exact hits work? Maybe 0 damage, maybe 1, maybe some special effect, not sure.

One downside I can see is that average damage is a bit higher than usual even for low-HD creatures, although this is somewhat countered by the fact that in my games, PCs don't die at 0 HP. The fact that high-level warriors deal lots of damage is a plus for me, especially because I don't like having many magic weapons.

The fact that people get used to thinking about margins of success could also be useful if you use this for skills and other checks, which I like.

Another problem is that big foes such as giants and dragons could have their damage significantly diminished if we use this system exactly as written, never being able to actually reach their "maximum damage". Maybe that's a problem for another day, but I can imagine we could have a size multiplier of ×2 to ×4 (maybe "3x6" instead of "6d6"), which could create an interesting effect: a giant will not often hit the fighter, but when he does the damage is massive — one mistake might cost him dearly!

I think I originally had this idea years ago, when playing bell-curve systems, which might have different, but interesting, effects.

There are probably another issues I'm missing, but so far I really like this idea... let me know what you think in the comments!