OSR: Rereading OD&D: Back to the Start

Time to revisit the primordial ooze of the Old-School Renaissance, the original D&D booklets.

While my usual long-term OSR campaigns use the GLOG, for playtests and one-shots I sometimes use a highly mutated version of AD&D. If they were dog breeds, the version of AD&D I use would be a neurotic greyhound with hip dysplasia, the GLOG is an Argentine tegu in a dog costume, and OD&D is a barely domesticated coyote/dog hybrid

I will not explain further.

No One Ever Said It Would Be This Hard

Imagine it's 1974ish. All you have are the three Little Brown Books: Men and Magic, Monsters and Treasure, and Underworld and Wilderness Adventures.

You have no wargaming experience. You have no access to magazines, groups, or official answers. No Chainmail, no Dungeon, no Dragon, no Greyhawk, no Judges Guild, no internet, no nothing. A mysterious robed figure gave you three booklets and some polyhedral dice and vanished in a puff of gedankenexperiment.

Can you run OD&D with the rules as written, without the benefit of errata, context, or decades of new rules?

Yes. Yes you can.

But there are a few edge cases that you may need to resolve along the way.

The Little Brown Books are probably the most thoroughly examined texts in RPG history. I can't claim any of the curious rules below are original discoveries, because they've almost certainly been debated half to death in long-forgotten forums or letters to the editor. They're still amusing, and might be new to a given reader.

The Original Intentions of What Later Became Dungeons and Dragons.

As I see it, Dungeons and Dragons was originally designed as an amusing diversion for the generals and leader-types of a wargaming-scale fantasy army. Imagine plucking a Warhammer character model off the battlefield and sending them on a short excursion, where they could potentially pick up an item to help them in a future battle.

Original D&D in many ways plays like a modern board game in the style of Betrayal at House on the Hill, but where you randomly generate your character instead of picking a card, and where there's a referee to handle situations like "Can I shoot the door open with a shotgun?" or "Can I throw this item down the stairs?"

The moment someone asked "Can a torch burn cobwebs?" or "Can I ask the Goblin about his past?", OD&D stopped being a formulaic exercise in micro-wargaming and became... well, OD&D. It became a shared imaginary world, where the rules and logic of our world applied, instead of a bloodless chess-like abstraction.

As befits a first attempt, OD&D contains many rules oddities that are worth examining. 

Ryan van Dongen

Strictly Orthodox Vampires

Vampires cannot abide the smell of garlic, the face of a mirror, or the sight of cross. They will fall back from these if strongly presented. -Monsters & Treasure

Notably, "holy symbols" are not present in OD&D. You can buy wooden or silver crosses. 10 items (arguably) on the basic equipment list are specifically related to the undead. Your job, or at least the Cleric's job, is to fight Draculas.

Interestingly, while you can buy Belladonna, Wolfsbane, and Holy Water, they don't have specified mechanical effects. Garlic does; holy water doesn't.

Overpowered Elves & Dwarves

Some of the advantages of playing an Elf or a Dwarf are not listed in Men & Magic, but hidden in the Monster section of Monsters & Treasure.

Elves have the ability of moving silently and are nearly invisible in their gray-green cloaks. Elves armed with magical weapons will add one pip to dice rolled to determine damage, i.e. when a hit is scored the possible number of damage points will be 2-7 per die. -Monsters & Treasure

Elven Cloak and Boots: Wearing the Cloak makes a person next to invisible, while
the Boots allow for totally silent movement. -Monsters & Treasure

This suggests, but does not completely confirm, that an Elf PC starts with an Elven Cloak and Boots. The +1 damage when using a magical weapon seems to be clear.

DWARVES: Because of their relatively small size, clumsy monsters like Ogres, Giants and the like will have a difficult time hitting Dwarves, so score only one-half the usual hit points when a hit is scored. -Monsters & Treasure

Note that this only applies to Dwarves, not Hobbits, Gnomes, etc. This is odd, because Gnomes are "slightly smaller than Dwarves." Perhaps their little Gnome legs are just too tiny to allow for quick dodges?

Xiaoyu Wang

All Hobbits Go To Heaven

Raise Dead: The Cleric simply points his finger, utters the incantation, and the dead person is raised. This spell works with men, elves, and dwarves only. -Men & Magic

What about Hobbits?

1. Hobbits don't have souls.
2. Hobbits automatically go to a better world and are reluctant to return.
3. Hobbits are already in heaven.
4. The moment a Hobbit dies, ethereal copyright lawyers from the Tolkien estate swoop in and destroy their soul.
5. Hobbits are a kind of monster that somehow, by tricksiness and cunning, snuck into the character creation rules. Since you can't use Raise Dead on monsters, you can't use it on Hobbits.
6. Anyone crazy enough to play a Hobbit doesn't deserve a second chance.

Fully Armoured Wizards

Magic-Users can, arguably, wear non-magical armour.

Magic-Users: Top level magic-users are perhaps the most powerful characters in the game, but it is a long, hard road to the top, and to begin with they are weak, so survival is often the question, unless fighters protect the low-level magical types until they have worked up. The whole plethora of enchanted items lies at the magic-users beck and call, save the arms and armor of the fighters (see, however, Elves); Magic-Users may arm themselves with daggers only.  -Men & Treasure

Clerics: Clerics gain some of the advantages from both of the other two classes (Fighting-Men and Magic-Users) in that they have the use of magic armor and all non-edged magic weapons (no arrows!), plus they have numbers of their own spells.

Elves: Elves can begin as either Fighting-Men or Magic-Users and freely switch class whenever they choose, from adventure to adventure, but not during the course of a single game. Thus, they gain the benefits of both classes and may use both weaponry and spells. They may use magic armor and still act as Magic-Users.

The rules explicitly prevent the Magic-User from wearing magic armour, but non-magical armour seems to be fine. Kit out your wizard in a set of plate and give them a shield; they'll need it.

The difference between a human Fighting Man, Cleric, and a Magic-User at level 1 is negligible. The MU casts one spell and turns into a Fighting Man with a dagger, 1 fewer HP, and slightly worse saves.

The weapon-and-armour restriction makes more sense if you view OD&D as a board game with various item cards in a deck. The basic equipment list is your pre-dungeon boring stuff; the real goodies are drawn from the deck, and MUs can't use some of the cards.

You're My Wonderwall

Scale in OD&D is a controversial topic. Most of the time, the books use a tabletop scale of 1" = 10'. Mixing real-world scales and tabletop scales in the same text inevitably leads to confusion.

In the underworld all distances are in feet, so wherever distances are given in inches convert them to tens of feet. -Underworld & Wilderness Adventures 
Wall of Stone: The creation of a stone wall two feet thick with a maximum length and height equalling 10 square inches. The wall will last until dispelled, broken down or battered through as a usual stone wall. Range: 6". -Men & Magic

Is the Wall of Stone:
a) 2' (24") thick in the real-world scale?
b) 2' (24") in tabletop scale, and therefore 240' thick in real-world scale?

"Aha," you say, "when the book writes 'feet' it means 'real-world feet' and when it writes 'inches' it means 'tabletop scale inches'."  

Well read on!

Wall of Iron: Like a Wall of Stone, but the thickness of the wall is three inches and its maximum area 5 square inches. Duration: 12 turns. Range: 6". -Men & Magic

Is the Wall of Iron:
a) 3" thick in the real-world scale?
b) 3" in tabletop scale, and therefore 30' thick in real-world scale?

"Aha!" you say, "when the book writes a number out in words (e.g three) it means 'real world inches' and when it uses a numeral (e.g. 3) it means 'tabletop scale inches'."

And that might make sense if that system was used in any of the other rules, but no, it's arbitrary in the other books. Yes, there is a sensible and obvious answer. No, you are not obligated to pick the sensible answer.

A Magic-User can, arguably, create a Wall of Stone that is:
Tabletop: 10" high, 1" wide, 24" thick.
Real World: 100' high, 10' wide, and 240' thick.

Behold! I am a mighty wizard! 

And, arguably, the spell becomes even mightier outdoors, where 1" = 10 yards = 30'... if you use the variable indoor/outdoor scale (which nobody does, because it's too much trouble).

Sighting Monsters: Players will see monsters at from 40-240 yards (inches convert to tens of yards for the wilderness) unless the monster has surprised the characters involved. -Underworld & Wilderness Adventures

Imagine such a world, covered in criss-crossing iron and stone walls, a labyrinth landscape scarred by wizard wars. Perhaps some small lakes from melting Walls of Ice (60'x20'x60' or 72,000 cubic feet, 538,000 gallons, or 2 million litres of water, or, amazingly, around 1 Olympic swimming pool).

Stepan Alekseev

Periodic Undead

The OD&D Wraith was invented solely to fill a gap on the HD chart.

WRAITHS: These monsters are simply high-class Wights with more mobility, hit dice, and treasure. Hits by silver-tipped arrows will score only 1/2 die of damage, and magic arrows only score 1 die of damage when they hit. -Monsters & Treasure

Clearly, it's not the most original monster. Why the book needed a strict 1:1 HD:Undead list is not entirely clear. Perhaps it has something to do with levelling up from a Skeleton to a Vampire. Nothing else in OD&D follows this systematic progression.

We'll be referring to these tables quite a bit.

HD-Based Combat Resolution 

In most post-OD&D games with descending Armour Class, like Old School Essentials, a Shield+1 is an extra -1 AC (-2 AC total). This makes intuitive sense and speeds up combat resolution.

In OD&D, it works slightly differently. A Shield+1 is -1 AC and subtracts 1 from the HD of the opponent.

Armor proper subtracts its bonus from the hit dice of the opponents of its wearer. -Monsters & Treasure


A PC with Chainmail+1 (AC 5) and a Shield+1 (AC -1) is fighting an Orc (1+1 HD).

AC subtraction (incorrect): PC has AC 2 (5-1-1-1). The Orc, as a HD 1+1 creature, hits AC 2 on a 16.

HD modification (correct): PC has AC 4 (5-1). The Orc's HD is reduced by 2 (one from the Chainmail+1, one from the Shield+1). As a HD "up to 1" creature, it hits AC 4 on a 14.

A PC with the best available armour in OD&D, Plate Mail+2 (AC 3)  Shield+3 (AC -1) (AC 2 total) is fighting an Orc (1+1 HD). 

AC subtraction (incorrect): PC has AC -3, which is not on the table.

HD modification (correct): PC has AC 2 (3-1). The Orc's HD is reduced by 5. As a HD "up to 1" creature, it hits AC 2 on a 17.

The same PC is fighting a Balrog (HD 10). The Balrog's HD is reduced by 5. As a HD 4-6 creature, it hits AC 2 on a 12.

The worst possible to-hit is a 17. You always have at least a 20% chance to hit.

This whole HD-reduction scheme makes a lot more sense if you have access to Chainmail's combat system, but we don't.

Ariel Perez

Helmets, Shields, and Hit Probability

In OD&D, there is a hidden pre-attack resolution step. Helmets are listed on the equipment list (Men & Magic), but do not have any rules provided. Their rules are implied.

Helm of Reading Magic and Languages: Wearing this helm allows the person to read any language or magical writing. It does not protect in the same way as Magic Armor, so if it is worn in combat any hit upon its wearer should be given a 10% of striking the helm and smashing it. -Monsters & Treasure

Shields also have separate rules.

If the shield's bonus is greater than that of the armor there is a one-third chance that the blow will be caught by the shield, thus giving the additional subtraction. -Monsters & Treasure


A PC with non-magical Chainmail (AC 5), a Shield+1 (AC-1), and no helmet (due to dripping green slime or thriftiness) is fighting an Orc (HD 1+1).

Before making an attack roll, the GM rolls 1d10.
On a 1, the attack hits the unarmoured head (AC 9, so 9 to hit).
On a 2-4, the attack hits the Shield+1 (AC 4, but -1 HD, so 15 to hit).
On a 5-10, the attack hits the Chainmail. (Still AC 4, so 14 to hit).

Combat is not swift, but it is amusing.

Furious Combat

How many times do monsters attack in OD&D?

Attack/Defense capabilities versus normal men are simply a matter of allowing one roll as a man-type for every hit die, with any bonuses being given to only one of the attacks, i.e. a Troll would attack six times, once with a +3 added to the die roll. (Combat is detailed in Vol. III.) -Monsters & Treasure

This suggest that a 6+3 HD troll attacks 6 times, with one attack getting a +3 bonus to the roll. This is (if we know about Chainmail) perfectly sensible, but we don't know about Chainmail.

Also, Combat is not detailed in Vol. III. At best, it's vaguely suggested in Vol. III.


A Troll (6+3 HD) attacks a Lord, 10th Level Fighting-Man with the best available armour in OD&D, Plate Mail+2 (AC 3)  Shield+3 (AC -1) (AC 2 total).

 The Troll attacks as a HD 1+1 creature (6-5) against AC 2, and needs a 16 to hit with 6 attacks, with one roll getting a +3 bonus, and with any hit dealing 1d6 damage. 

A Lord, 10th Level Fighting-Man has 10d6+1 HP. Trolls appear in groups of 2-12.

Clearly, something has gone awry here. All the other rules, and common sense, suggest that monsters attack once unless otherwise specified.

In Melee the Centaur will attack twice, once as a man and once as a medium horse. - Monsters & Treasure
Giant Crabs: As these creatures cannot swim, they are a peril only near beaches and on land. They travel 6" per turn. They attack twice, once for each pincher, and can take from 3 - 18 points of damage. - Underworld & Wilderness Adventures

Still, it's amusing to imagine a non-Chainmail combat system using high-powered blender-like monsters. OD&D rocket tag. A Wraith that makes four attacks, each one draining a level on a hit? Get me out of this dungeon!

Adrian Smith

Giant Strength and HD Modification

Gauntlets of Ogre Power: These gauntlets give the wearer the ability to strike as an Ogre and generally give his hands and arms the strength of an ogre. They do not necessarily increase hit probability however. -Monsters & Treasure

Girdle of Giant Strength: Wearing this device bestows the strength and hit prob-
ability (if greater than the wearer's own) of Hill Giant -Monsters & Treasure

In OD&D, Strength (the characteristic) does not give any bonus to damage. Gygax houseruled this pretty early on, but we don't have access to those rulings.

The Gauntlets of Ogre Power let a PC act as a HD 4+1 creature (equivalent to a level 7-9 PC) for hit probability, unless their hit probability is higher. If you're a level 10 PC, then the gauntlets won't do you any good. Perhaps the GM could rule they're useful for cracking the necks off wine bottles or bending fireplace pokers into pretzels.

The Girdle of Giant Strength lets the PC act as a 8 HD creature (which oddly doesn't have an equivalent on the PC hit table) for hit probability, unless their hit probability is higher.

GIANTS: As stated in CHAINMAIL, Giants act as mobile light catapults with a 20' range. Due to their huge weapons all Giants will score two dice of damage when hitting an opponent. -Monsters & Treasure

So, in OD&D, if you have a Girdle of Giant Strength, you are as strong as a Hill Giant. You can, presumably, act as a mobile light catapult with a 20' range, but in melee you don't deal 2d6 daamge instead of 1d6 unless you are wielding a huge weapon.

How much does a huge weapon weigh in gold pieces? If we're being strict, a Girdle of Giant Strength doesn't increase a character's carrying capacity beyond the standard 1,500gp limit. After all, the Gauntlets of Ogre Power apply to the hands and arms, not the back, spine, and hamstrings.

On the other hand, "Wandering Giants will carry from 1,000 to 6,000 Gold Pieces with them in their usual copious shoulder sack" (Monsters & Treasure), so maybe your carrying capacity is increased to 6,000gp.

Filipe Pagliuso

Hold It Right There

If you're used to Hold Person as a "lock in place"-type spell, OD&D's version might be a bit confusing.

Hold Person: A spell similar to a Charm Person but which is of both limited duration and greater effect. It will effect from 1-4 persons. If it is cast at only a single person it has the effect of reducing the target's saving throw against magic by -2. Duration: 6 turns + level of the caster. Range: 12". 

Charm Person and Charm Monster are two of the most powerful spells in OD&D, as they give you a permanent hireling (and a hilarious melee-range liability if the spell is ever dispelled).

Charm Person: This spell applies to all two-legged, generally mammalian figures near to or less than man-size, excluding all monsters in the "Undead" class but including Sprites, Pixies, Nixies, Kobolds, Goblins, Orcs, Hobgoblins and Gnolls. If the spell is successful it will cause the charmed entity to come completely under the influence of the Magic-User until such time as the "charm" is dispelled (Dispell Magic). Range: 12"

Charm Person: 1 target, permanent.
Hold Person: 1-4 targets, 6 turns + level of caster.

Charm Monster: The counterpart of a Charm Person spell which is employable against all creatures. If animals or creatures with three or fewer hit dice are involved determine how many are effected by the spell by rolling three six-sided dice. It is otherwise identical to the Charm Person spell.

Hold Monster: Same as Hold Person but applicable to Monsters.

Charm Monster: 1 monster or 3d6 total HD of monsters with 3 or fewer HD, permanent.
Hold Monster: 1-4 monsters, 6 turns + level of caster.

You could argue that Hold Monster would work on 12d6 total HD of monsters with 3 or fewer HD.

Ville Sinkkonen

Final Notes

Do you have a favourite weird OD&D rule? Have I made a terrible mistake in my interpretation of the sacred texts? Post your feedback in the comments.


  1. Love the idea that you work your way up through the different kinds of undead, the skeleton slowly packing on more flesh up to the level of a wight, leaving their decaying shell to become a spectre, making a proper custom-made corpse and becoming a mummy, trading that for an even better spectral form, and finally getting a nearly-human nearly-living body as a vampire. There's something there, maybe, if you trim some of the loops away.

    1. Yeah! I expanded the concept into a HD(NA) chart for the AD&D MM, MMII, and Fiend Folio here: https://coinsandscrolls.blogspot.com/2019/10/osr-hdna-of-monster-manual-mmii-fiend.html
      And I incorporated the idea into a table in my bestiary, the Monster Overhaul. You can see a draft version here: https://drive.google.com/file/d/1EUctF5dpOokaOvJmVskR5K0xWZEdujUg/view

      It makes for a fun game. Start out a something low level and work your way up.

  2. You forgot to mention that at high level fighters can detect invisible automatically. :)

    1. Really? Explain please.

    2. Ah from Chainmail, of course. I was looking through the LBBs to try and find a stray reference, but it's not in there. It's in Chainmail only.

    3. It's there in the LBBs too, but hidden within the Pixie entry in Monsters & Treasure: "They can be seen clearly only when a spell to make them visible is employed, although certain monsters such as Dragons and high-level fighters will be aware of their presence."

    4. Aha! That's the kind of detail I'm looking for. Thanks! Good stuff!