Holmes and the Combat Turn

 

There are relatively few clues given in the 3LBBs about the structure of original D&D’s combat turn, and what other clues exist are scattered through early D&D artifacts that are mostly pretty hard to come by. However, the “Second Combat Example” appearing in Holmes is one of the more detailed (and readily accessible!) accounts of the original D&D combat turn that we have in print today.

The blue book (a.k.a. “Holmes”) was published in July 1977, some three and a half years after the original D&D boxed set. However, it must have been in development for a good while prior to that. The final Holmes manuscript mentions Gods, Demigods & Heroes by name (published in July 1976), so that manuscript must have been created post July 1976, and prior to July 1977. EGG suggests (albeit indirectly) in commentary printed in Dragon #5 (December 1977) that the Holmes project may have begun as early as December 1975:

Two years ago we determined to revise the whole of D&D in order to clean up the errors and fill in the holes. The project is a long and complicated one, a task not accomplished overnight.
EGG —Dragon #11, December 1977

Regardless of its precise inception date, it is clear that Holmes was devised during original D&D’s hey-day, and that it is a neat representation of an important part of those rules. It is, perhaps, the first original D&D clone in today’s sense of the term—counter edited by EGG to boot.

Holmes Second Example

So let’s take a look at the first paragraph of Holmes’ famous example. The text below is as close as I can make it to the final Holmes manuscript—as presented by Zenopus in his fantastic analysis, here. Differences from the printed version (p21 of the blue book) are highlighted in bold:

SECOND EXAMPLE
A party of adventurers is standing at an intersection of corridors when the Dungeon Master rolls a “wandering monster.” Using the Wandering Monster Table, he determines that the party is being attacked by six giant spiders with 1 hit die each and they are 100 feet away. “Flubbit” the magic-user throws a sleep spell but it only affects four of them, the other two keep coming. The party decides to fire arrows, the Dungeon Master rules that only those in the front row have a clear field of fire. The spiders are 50 feet away and coming fast. Two characters get off arrows from their long bows and they agree to both shoot at “the one on the left.” They roll a 3 (an obvious miss) and a 15. The spiders are armor class: 3 (plate), but the range is medium for the longbow, the 15 is a hit and is found to do 4 damage points. The spider’s hit die is rolled and comes up a 4–the creature is killed by a lucky arrow hit! The second spider keeps coming. The archers get off one more arrow apiece, an 8 and a 12, and the shafts bounce off the beast’s armor. The two fighters drop their bows and draw swords as the monster is upon them, biting!

Lovely.

Meet: the Simultaneous Movement System

Okay, so now let’s explore the Second Example blow by blow, assuming (yeah, the usual heresy) that:

  1. The basic system is that from CHAINMAIL” (U&WA p25), and furthermore let’s assume CHAINMAIL’s Simultaneous Movement System (CM p9), and
  2. Surprise gives the advantage of a free move segment” (U&WA p9) really means a free turn segment, and
  3. Two moves constitute a turn” (U&WA p8), and furthermore let’s assume there are two moves per combat turn (more on this in a later post).

The beginning is frequently a good place to start, so…

A party of adventurers is standing at an intersection of corridors when the Dungeon Master rolls a “wandering monster.” Using the Wandering Monster Table, he determines that the party is being attacked by six giant spiders with 1 hit die each and they are 100 feet away.

The 100ft encounter distance is notable for two reasons;
Firstly, player light sources typically have a 30ft radius, but since visibility is not otherwise mentioned in the example we might presume the area is lit.
Secondly, unlike OD&D Holmes has random encounters occurring at 20–120ft distance regardless of whether surprise occurs. This is an important nuance, below.

“Flubbit” the magic-user throws a sleep spell but it only affects four of them, the other two keep coming.

It is significant that the player spell is the very first action of the combat turn. For this to be the case, the players must have won a surprise segment and employed it as a missile/magic segment. Without surprise, we would have expected to see the example go immediately to the first movement segment, but we did not.

Note, however, that the unaffected spiders “keep coming”. That they “keep” coming implies they were already on the move as Flubbit threw his spell, which is at odds with the notion of a surprise segment.

Significantly, they didn’t require a morale check after two-thirds of them were magicked (presumably due to their limited intelligence).

The party decides to fire arrows, the Dungeon Master rules that only those in the front row have a clear field of fire. The spiders are 50 feet away and coming fast.

Importantly, the spiders have already closed to 50ft before the players loose their arrows. This must be the result of their first move (of two possible moves) during their movement segment. The movement segment is formally the first segment of each combat turn, so this is presumably demarks the beginning of the first regular combat turn.

It is also curious the spiders cover 50ft. Holmes gives the 1 HD variety of fantastic spiders a movement stat of “60ft per turn”. This most likely implies a 6″ movement rate in OD&D terms, so it may have been better stated as “60ft per move“. None the less, 50ft is within the spiders’ possible movement distance of 60ft.

Two characters get off arrows from their long bows and they agree to both shoot at “the one on the left.” They roll a 3 (an obvious miss) and a 15. The spiders are armor class: 3 (plate), but the range is medium for the longbow, the 15 is a hit and is found to do 4 damage points. The spider’s hit die is rolled and comes up a 4—the creature is killed by a lucky arrow hit! The second spider keeps coming.

Now our two fighters fire their first round of arrows, after the spiders have already covered 50ft of ground.

Note that 50ft range is erroneously said to be medium range for longbows. In fact, the target would have to be at least 70ft away to qualify as medium range for a longbow. This is important because–according to the Holmes attack matrix–a 1st level fighter requires a throw of 16 to hit AC 3 (plate), with short range adjusting the throw by +1. Thus, a throw of 15 would be a miss at medium range, but a hit at short range.

This round of missile fire could possibly represent pass through fire during the spiders’ movement segment, but because the subsequent round of missile fire (see below) must necessarily be pass through fire, this first round of missile fire can only have occurred during the surprise segment, before the spiders’ fist move. It should therefore have occurred at 100ft range–which would have correctly been at medium range, as stated in the example.

The second spider keeps coming.

This must be the spider’s second move (of two possible moves) during its movement segment. This movement results in melee contact (see below) because the spider covers the remaining 50ft of ground to contact the players.

It is worth noting that melee contact occurs at 1″ range (for man-sized figures), so the spider needed to cover only 40ft in its second move to achieve melee contact. Additionally, CM and OD&D allow most man-like figures a 3″ bonus to their movement speed when charging into contact. This detail is ignored in the Holmes example.

The archers get off one more arrow apiece, an 8 and a 12, and the shafts bounce off the beast’s armor.

This second round of missile fire from the players is potentially problematic because the spider’s second move results in melee contact.

According to CM (and hence OD&D) melee contact disallows any further missile fire. Therefore, this second round of missile fire can only legally have occurred as pass through fire during the spiders’ movement segment—between their first and second moves. For this to be the case, the first round of missile fire (above) must have occurred during the surprise segment, before the spiders’ first move.

The two fighters drop their bows and draw swords as the monster is upon them, biting!

Now that melee contact has occurred, and we enter the melee segment. Our front-most pair of fighters now drop their bows to change to melee weapons, losing the opportunity to attack in the first round.

If there were a second rank of fighters ready, and sufficient room behind them, our front-most missile-men technically could have refused combat and withdrawn behind them. However, that is not the subject of this post.

Analysis

What have we learned?

Despite there being a few question marks around surprise and the precise sequence of missile fire, Holmes’ famous combat example is generally explainable in terms of CM’s Simultaneous Movement System in the context of D&D. Importantly, it is possible for the magic-user to throw his spell first (with surprise), and for the archers to fire two volleys before melee contact occurs.

The obvious questions are then whether the same outcomes can be achieved without requiring surprise, and/or with just one move per turn. That will be the topic of my next post