Last year, I've read a Reddit user (Kubular) talking about a single attack/damage roll, and ever since I cannot stop thinking about this.
Just roll 1d20, add your attack bonus, a "weapon rating" (WR) and subtract AC: this is the total damage (minimum 0).
(I'm assuming ascending AC here; if you're using THAC0, add AC and subtract THAC0, etc.)
Example: if you roll 15, your attack bonus is +4, and your WR is +3, your total is 21. Against AC 17, this means 4 points of damage. But against AC 10, you deal 11 damage!
This has innumerable benefits.
- One fewer roll, for starters. Faster combat.
- It prevents the disappointment of "I rolled a 19 in my attack - perfect! Roll damage... 1 point... sigh...".
- Armor becomes immediately vital. When unarmored, being hit by a dagger (held by a capable fighter) is DEADLY even at mid-levels.
- At the same time, weapon choice becomes more important against armored foes, beyond a simple +1 damage.
- Bigger weapons are better, but even MORE relevant against armored targets - going back to CHAINMAIL days.
- Fighters become more deadly as they progress WITHOUT the need of multi-attacks. Conan can now kill an unarmored sorcerer with a chair, or with a single blow of his sword.
- Lines up perfectly to the AD&D advice (IIRC) that excess bonuses after you "always hit" go to damage (e.g., if you had +15 to hit against AC 11, you immediately add +4 to damage).
- It is also perfect for B/X, where a fighter will rarely have an attack bonus much greater than +10, so things never get out of hand.
- This lines up well with the idea that monster damage raises on average one point per HD, something Gygax suggested and I have discussed in this blog before.
- It can also reduce monster stats; their damage is derived from their attack bonus/HD, no need to list damage for most monster attacks (and two attacks could just get -2 each, thus reducing to-hit AND damage and sometimes creating an interesting choice - attack more often if your opponent has weak armor, etc.).
- Now the bonus to attack/damage is a single number. Str gives you +1 to attack/damage, and a magic weapon might give you an additional +2 attack/damage. B/X already does this; now, weapon damage follows the same pattern.
- There is always a small chance of near failure. Even a lowly goblin can survive a blow from a +5 sword if the attacker rolls badly.
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| Source: stupidcircus on Facebook. |
Calculating damage is a bit tricky.
Basically, if you hit on a 11+, you have 50% chance to hit, and your average damage when you do is 4.5 (the average of all possibilities, from 0 damage on a natural 11 to 9 on a natural 20) - so average DPR is 2.25 (see table below).
If you ALWAYS hit, average damage AND DPR is 9.5.
If you need a nat 20 to hit, since the difference is ZERO, you can cause no damage - of course, you could rule that the MINIMUM damage is 1, so the DPR would be 0.02.
As you can see, average damage is nothing absurd - even if maximum damage varies wildly.
DPR is lowered against heavy armor, and augmented against unarmored foes.
For example, a d4 dagger usually has a DPR of 1.25 if you need to roll 11+, but if you use this system and consider the dagger a +1 weapon, the DPR goes to 2.75 (since you hit on a 10+).
|
Roll needed |
1 |
2 |
3 |
4 |
5 |
|
Dmg |
9.5 |
9 |
8.5 |
8 |
7.5 |
|
DPR |
9.5 |
8.55 |
7.65 |
6.8 |
6 |
Roll needed |
6 |
7 |
8 |
9 |
10 |
|
Dmg |
7 |
6.5 |
6 |
5.5 |
5 |
|
DPR |
5.25 |
4.55 |
3.9 |
3.3 |
2.75 |
Roll needed |
11 |
12 |
13 |
14 |
15 |
|
Dmg |
4.5 |
4 |
3.5 |
3 |
2.5 |
|
DPR |
2.25 |
1.8 |
1.4 |
1.05 |
0.75 |
Roll needed |
16 |
17 |
18 |
19 |
20 |
|
Dmg |
2 |
1.5 |
1 |
0.5 |
0 |
|
DPR |
0.5 |
0.3 |
0.15 |
0.05 |
0 |
There are also potential shortcomings.
- Punches could become too deadly, even if you rate them as -4.
- Likewise, unarmored targets are very frail. Barbarians, monks, or maybe EVERYONE might need a small AC boost at higher levels.
And some ways to spice/fix things up.
- Maybe weapons are +1/+2/+3/+4, with swords giving you +1 damage and maces giving you +1 attack and -2 damage (so they are better against armor), etc.
- Maybe there is a soft limit to damage (e.g., 5/10/15/20), so strong fighters benefit more from bigger weapons.
- Instead of assigning bonuses to weapons, just roll a d4/d6/d8 etc. So, d20+d4+attack bonus for a dagger, and so on, making things even more swingy and deadly. Maybe use unarmored AC 12 to balance things out.
Would I use this in my B/X games? I'm not sure.
I think it would be a great fit for a "Song of Ice and Fire" type of campaign, or maybe some gritty Sword & Sorcery.
I'm not sure my players would buy the idea for traditional D&D games - they are just too used to rolling damage.




