AC vs THAC2 arms race

[waysoftheearth]

Here's a random thing I did just now with Attack Matrix 1:

The average AC of monsters (excluding slimes and horses) appearing in M&T with up to 3 HD is around 6; a 1st to 3rd level fighter needs to throw a 13+ on a d20 to hit AC 6; so I circled the "13" in the 1st column.

Rinse and repeat for the next three columns:
The average AC of monsters appearing in M&T with up to 4-6 HD is around 4; so in the 2nd columm I again circled "13".
The average AC of monsters appearing in M&T with up to 7-9 HD is around 3.1; so in the 3rd column I circled "11".
The average AC of monsters appearing in M&T with up to 10-12 HD is also around 3 (2.7); so in the 4th columm I circled "9".

Okay, so now we have a visualisation of "the arms race" between AC and "to hit" scores in Attack Matrix 1 terms.

What does it all mean?

Nothin at all. But it is kinda interesting to see how "to hit" improves relative to monster AC.

Broadly, what this shows is: in normal and heroic tiers (1st and 2nd columns)--arguably where most play happens--fighting men hit equivalent tier monsters around 40% of the time. In the superheroic tier (3rd and 4th columns) fighting men hit equivalent tier monsters 50% and 60% of the time, respectively. Magic weapons probably improve the superhero's odds further. Details aside, you would not be "far off" if you simply ruled that fighters hit equivalent tier monsters 50% of the time. Sure, there are a handful of exceptions (e.g.; dwarves have better armour; slimes and medusea are squishy; wraiths and spectres are hard to hit; unicorns are hard to hit).


That said, it seems clear that monster AC falls off relative to fighter to hit in the 3rd and especially in the 4th column. Maybe in part because, with a "ceiling" of AC2, there's hardly anywhere for higher HD monsters left to go? Anyways, if we're sticking to the ACS we might consider fiddling monster ACs so that the average "to hit" required in each of the first four columns is a more linear progression. Perhaps an average "to hit" score around 11 (50% chance of a hitting) in each column would work? This would "require" average monster ACs around 8, 6, 4 and 2 for HD equivalents to the first four columns.

On the other hand, that sounds like a bunch of work. If I was lazy it might be a lot simpler to just assume a 50% chance (3-in-6?) of hitting an "equivalent tier" monster, with higher tier monsters and a handful of exceptions (e.g., dwarves, wraiths, spectres...) being harder to hit. But then we don't need "AC" and "What about my armor??". I guess a figure wearing "enough" armor would be "hard to hit" (like dwarves).

Or not. Ha!

Dunno, I haven't thought any of that last bit through; open to suggestions

[Finarvyn]

I'm not sure what you discovered, either, but I like the way your mind is working on this. I'll have to ponder it further.

[noteef]

Very nice analysis. I need time to process as well.

The first thought that popped into my mind is fighting-men need greater chances to hit higher HD monsters because monsters take so many more hits.

Plus, it is their thing, just like cleric and magic-user spells sharply increase in power.

[talysman]

I think rather than changing the "to hit" roll to eliminate the need for armor, based on that info, I'd go more with setting a default AC based on HD for monsters that don't wear armor.

This is kind of what I'm doing in the undead supplement I'm working on. I have a table like this, at least for now:

Rank	Title	Dice	Armor	Damage
0	Relic	1-3	None	None
1	Corpse	up to 2+3	Light	1
2	Wight	3-1 to 4+3	Medium	1
3	Master	5-1 to 6+3	Medium	1+1
4	Lord	7-1 to 9+3	Heavy	2-1
5	Elder	10-1 to 12+3	Heavy	3
6	Ancient	13 and higher	Extreme	3+1

I do have some variation built into the system, so it's possible to face 2 HD walking corpses with Medium armor (AC 5) instead of Light armor (AC 7).

[derv]

I'll just add my own brain fart as well. No real analysis went into this, but.....

Fighting Men generally make the best comparison because of their HD progression. Where you cap level progression effects the average. It appears that 10 was likely in mind. I'll use the Purple Worms 15 HD as a cap for monsters.

Level (equivalent monster HD)= easier to hit things
AC= harder to be hit
HD= harder to be killed

average level FM= 5
average HD monster= 8
average AC= 5 (chain)

conclusion: level 8 FM should hit average foe 50%

HD 5 monster should hit average FM 50%

Progressions should step up or down from those averages.

[Deleted]

I noticed this trend as well as the reverse trend (where PCs need to keep their AC constantly improving just to keep it at the same effectiveness). It's the primary reason why I set the number needed to hit to 11+ Monster's HD. That way, a fighter and an equally leveled monster hit each other about 50% of the time regardless of level.

[waysoftheearth]

Aug 3, 2019 20:50:39 GMT -6 @hedgehobbit said:

I noticed this trend as well as the reverse trend (where PCs need to keep their AC constantly improving just to keep it at the same effectiveness). It's the primary reason why I set the number needed to hit to 11+ Monster's HD. That way, a fighter and an equally leveled monster hit each other about 50% of the time regardless of level.

Great work @hedgehobbit

It's interesting that your method at "HD level" of granularity (1 pip of THACx on a d20 per HD) is similar to what I described at the "tier level" of granularity (1 pip of THACx on a d6 per tier), only more detailed. Seems to me like a "tier" (a column on AM1) is 3 fighter levels/3 HD wide, and that 1d6 also just happens to be about one-third of a 1d20, so it scales kinda neatly. I love it when stuff like that works out

[Zakharan]

Thoughts along these lines had me very interested in running something akin to Warriors of Mars. Calculating hit odds based on difference in level is very simple.

[retrorob]

Aug 4, 2019 18:20:06 GMT -6 Zakharan said:

Thoughts along these lines had me very interested in running something akin to Warriors of Mars. Calculating hit odds based on difference in level is very simple.

That's why I use Damage Dice from EPT and initative rules from Warriors of Mars in my OD&D games. Basically high-level Fighters mow weaker opponents. It's very simple and speed up the game considerably

[Fearghus]

Aug 16, 2019 5:34:48 GMT -6 retrorob said:

Aug 4, 2019 18:20:06 GMT -6 Zakharan said:

Thoughts along these lines had me very interested in running something akin to Warriors of Mars. Calculating hit odds based on difference in level is very simple.

That's why I use Damage Dice from EPT and initative rules from Warriors of Mars in my OD&D games. Basically high-level Fighters mow weaker opponents. It's very simple and speed up the game considerably

Could you speak a little as to how initiative in Warriors of Mars of works? I am not familiar with it.

[retrorob]

Fearghus

In individual combat (man-to-man and man-to-animal) there are no rolls.

1. Movement
2. Missile
3. Melee

The most complex is the melee part:

Blows are given according to iniative. To determine which figure strikes first the following priorities are used -- 1. supercedes all others; 5. is used only when all others do not apply.
1. If one figure surprises the other (ambush, flank attack, rear attack, etc.) it strikes first.
2. The figure with the longer weapon strikes first.
3. The charging figure strikes first if weapons are of equal length or if the defender's is shorter.
4. If man vs. animal the man strikes first (he needs it!); if man vs. man the figure with the higher level of ability (13th, 12th, 11th, and so on down) strikes first.
5. The figure which did not just move strikes first.

As always I got some doubts here. "The charging figure" is basically "Attacker" from CHAINMAIL. So who is the attacker?

waysoftheearth

sorry for going off topic, maybe you could crop these posts as a separate thread.

[Zakharan]

Aug 16, 2019 7:19:06 GMT -6 Fearghus said:

Aug 16, 2019 5:34:48 GMT -6 retrorob said:

That's why I use Damage Dice from EPT and initative rules from Warriors of Mars in my OD&D games. Basically high-level Fighters mow weaker opponents. It's very simple and speed up the game considerably

Could you speak a little as to how initiative in Warriors of Mars of works? I am not familiar with it.

Initiative in the first turn is mostly determined by weapon length and who moved first. The roll is handled by the victim. If they survive, they roll to "attack," and if they succeed they gain initiative and may attack next turn. You also automatically seize initiative every 3rd turn.

[retrorob]

Aug 16, 2019 14:44:36 GMT -6 Zakharan said:

Aug 16, 2019 7:19:06 GMT -6 Fearghus said:

Could you speak a little as to how initiative in Warriors of Mars of works? I am not familiar with it.

Initiative in the first turn is mostly determined by weapon length and who moved first. The roll is handled by the victim. If they survive, they roll to "attack," and if they succeed they gain initiative and may attack next turn. You also automatically seize initiative every 3rd turn.

Oh, I forgot about this part. For clarification: the above quotation (surprise, weapon length, charge etc.) is the way to determine who gets the first attack only. Later the procedure is as laid out by Zakharan - it's complicated (a lot of rolling 3d6), but interesting (it is not simple blow-for-blow).