O5R: converting TSR-D&D monsters to 5e-D&D... WITHOUT changing the stat-line

This is my (very easy) OSR/TSR to 5e conversion, without changing the actual stats:

Suggested stat line (inspired by RC and S&W):

Goblin. AC 6 [13], HD 1d6; Move 30'; Atk Spear (1d6); Save F0; Morale 7.
Ogre. AC 5 [14], HD 4d10; Move 30'; Atk Club (1d6+2); Save F4; Morale 7.

5e conversion:
AC: as written [in brackets].
Move: as written [in brackets, if there are two numbers].
HP: maximum possible HP. If the HD indicates a single number instead of a type of die (for example, 3 inttead os 3d6), multiply HD by a number based on size: 6 for goblins, 8 for human, 10 for ogre/troll, 12 for giants/dragons, 20 for gargantuan creatures.
Damage: always deal maximum damage.
Bonus to hit: equal to HD.
Saves: bonus equal to the number indicated in two saves, as appropriate; usually Strength & Constitution for F, Wisdom & Intelligence for M, Dexterity & Intelligence for T, etc. Otherwise, halve the bonus.

Examples:

A monster that saves as F8 would have +8 bonus to Strength and Constitution saves, +4 bonus otherwise.

The goblin mentioned above would have a 6 HP and deal 6 damage per attack, while the ogre would have 40 HP and deal 8 points of damage per attack.

by Russ Nicholson

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And this is the (horribly difficult and convoluted) way I used to reach these conclusions:

I'm turning my old one page dungeon into a 30ish-pages module, and since I play both 5e and B/X, I was considering making it compatible with both (plus Dark Fantasy Basic, which is supposed to be compatible with B/X anyway).

I'm playing with the idea of having a single line of stat for BOTH systems. Thought it might be possible with some abbreviations and conversion. So I started playing with this idea.

Not that such type of conversion is necessary: we already have plenty of monsters for BOTH systems, and the easiest way to "convert" is finding a similar monsters. The thing is, I LIKE playing with numbers. So here we go!

I'll usa a goblin, an ogre and a large/adult red dragon as examples, just because. The numbers are from the RC, and the math is mostly done in my head as I write so... let me know if I got it wrong.

Armor Class

This one is actually not hard: just use an abbreviation such as "as leather" or "as plate+6", or even "as leather+1". Of course, armor and shields function differently in each edition - armor and shields provide a bigger bonus in 5e, which makes things more difficult.

Converting the actual numbers isn't hard either: jus subtract RC AC from 19 and you're good to go. The results are far from perfect:

AC	RC	5e (RAW)	5e (19-original)	5e (armor based)
Goblin	6	15	13	Scale (14)
Ogre	5	11	14	Chain (16)
Red Dragon	-3	19	22	Plate+6 (24)

One problem is that that dragons have AMAZING AC in old school D&D - a purple worm (also 15 HD) has AC 6 ("scale"), for example (9 points worse than the dragon), while in 5e the AC is almost the same (18 versus 19).

Another problem is that in 5e armor scales with CR, which doesn't happens as much in the RC. So, the purple worm has the same AC as a Minotaur in the RC, but in 5e, it beat the Minotaur 18 against 14.

Sigh. Let's just stick to the formula for now. So, the dragon has AC -3 [22], if we're using S&W notation.

Hit Dice (and "THAC0")

Here is the crux of the matter: 5e doesn't use HD in exact the same way as TSR-D&D. But it's there - and its useful. Let's compare:

HD	RC (d8)	5e (RAW)
Goblin	1-1 (S)	2d6
Ogre	4 + 1 (L)	7d10+21
Red Dragon	15 (L)	19d12+133

As you can see, 5e numbes are heavily inflated when compared to RC. The number of HD is nearly doubled (the 5e dragon has 19 HD, but lots of extra HP).

However, HD is used in two ways in the RC: to generate hit-points and to-hit bonuses (equivalent to "THAC0").

HP in 5e is WAY higher than the RC, specially at higher levels. However, if we break from the RC conventions and make HP vary with size like 5e suggests (say, 1d6 for goblins, 1d8 for humans, 1d10 for ogres, 1d12 for adult dragons, 1d20 for ancient dragons and purple worms), we could use the HD listed in the RC but giving MAXIMUM HP to each creature. So, the 15 HD dragon would have 180 HP (15x12). With the added AC, he would be a bit tougher than the 5e one, as long as we improve his saves, too.

HP	RC	5e (RAW)	5e (our formula)
Goblin	3.5	7	6
Ogre	19	59	41
Red Dragon	67	256	180

"To-hit" can simply be based in HD, like many OSR enthusiasts suggest: 5 HD means +5 to-hit etc.

"To-hit"	RC	5e (RAW)	5e (our formula)
Goblin	~+1	+4	+1
Ogre	~+5	+6	+4
Red Dragon	~+10	+14	+15

If a "Save DC" is needed, we will use the same number, plus 10.

Move

This is easy; 5e uses the number in brackets. 

So a Move 90' (30') ogre would move 30' in 5e. Maybe just get rid of the 90' and say you move three times faster when outdoor, etc. "As human", "as human x 2", etc, would work wonders in this case.

Attacks/damage

Damage tends to be higher in 5e, since HP is also a lot higher. This isn't that easy to convert. The best simple/elegant solution I could find is this: like with HP, 5e monsters deal the same damage as written in RC, but always maximum damage. So instead of 1d6+1 we got 7, and instead of 2d4+4, 12.

Saves

The RC simply indicates a class and level instead of a number; for example, F12 for a monster that saves as a 12th level fighter. 5e has certain classes being proficient in certain saves: Strength & Constitution for Fighters, Wisdom & Intelligence for Wizards ("Magic-users"), etc. 

We could always use Ref/Fort/Will , but that would be neither here (5e) nor there (OSR/TSR).

There are just so many monsters that have simply "Fx" in their saves, "x" being their HD, that I'm tempted of just getting rid of this line too.

XP/Treasure/etc

No conversion. I'd rather used circumstances/location to find treasure, and HD to calculate XP.

In conclusion...

Not an easy task, but doable. Now I can convert old school monsters on the fly. It is unlikely that I can publish a book with the same stats for B/X and 5e, but I could easily run an old school module for 5e characters without preparing the stats.

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ONE THOUSAND MAGE CLASSES with six simple choices

(discussing ideas similar to this post).

So, 5e has wizards, sorcerers, warlocks, druids, clerics, not to mention paladins, rangers, arcane knights, and so on. It seems everyone has some access to spells. Which is okay I guess - D&D is a game about magic after all (one day I'll write a post about that, but, consider: there are less than 30 types of melee weapons in the game, and half a dozen fighting styles, but more than 300 spells and as many magic weapons).

However, I the distinction between sorcerers and wizards and warlocks and clerics and druids etc... doesn't really convince me. This is not about 5e, but D&D as a whole; I'm using 5e to illustrate.

The sources of power are different. One studies books to get spells, the other one has spells given by a patron, other by a deity (what if the patron is a deity?), other has magic running in their blood (why can't THEY have any advantages when finding a patron or studying spells), etc.

Each class is tied to one ability: Intelligence, Wisdom or Charisma (you can do a muscle-mage or something, but lest stick to the basics here). Ok, the "smart"mage must have Intelligence, but why does the guy that makes deals with obscure deities be so charismatic? Sure, you could say he sweet-talked the ancient demon in giving him powers... but using ancient books to find a demos's true name and binding it is a viable alternative, right? Or at least a cool idea. Of course, Wisdom is usually better than Intelligence or Charisma for reasons discussed here.

There are also spell slots/spell lists. Some classes get more, some classes recover faster, and some can even create new slots on the fly... But there is no reason for the "smart" wizard to be unable to trade some additional spell slots for the ability to recover them faster, for example. Likewise, there are spell lists: some are huge, some are reasonably small, and some are very thematically defined - but it's all quite arbitrary nonetheless.

There are also taboos. Druids cannot wear metal armor. Wizards cannot cast spells in armor (unless proficient). And so on.

Of course, 5e has usually no consequences for spell-casting (except for the Wild Magic table but... those are really bad... which is a whole different subject). My Dark Fantasy Basic has some: you can enrage a deity, cause a spell mishap, forget spells, etc. But, again, this choice doesn't need to be tied to past choices: you could forget a spell that was given by your deity, for example.

In short: there are endless combinations to create with those distinct pieces.

d6	Source	Taboos	Consequences
1.	Study	Limited Weapons	Insanity
2.	Deities	Limited Armor	Forgetfulness
3.	Spirits	Limited weapons/armor	Enraged Deity
4.	Ancestry	Pacifism	Spell mishap
5.	Artifacts	Sacrifice	Exhaustion
6.	Accident	Poverty	Demon Summoning
d3	Spell list	Ability	Spell slots
1.	Huge	Wisdom	Many
2.	Medium	Intelligence	Some
3.	Small	Charisma	Few

We have more than ONE THOUSAND combinations right there, even if you forbid the most powerful ones (say, for example that Wisdom casters must have few spell slots or a small spell list, or disallow a huge spell list with many spell slots, etc).

Source.

Let's try a few that aren't in 5e:

- An Int-based Cultist who gets his spells from Chthonic deities, has limited weapons and armor and is subject to insanity.
- A Wis-based Reality Bender who can shape reality through sheer willpower, but cannot used all weapons and get exhausted if his powers are pushed.
- A Cha-based Shaman who communicates with the spirits of the wild, with limited armor, and prone to calling the attention of angry spirits by accident.
- An Int-based White Mage who uses his arcane knowledge of ancient texts to cure the wounded.

Etc.

And let's try one that I've just generate randomly: 3, 4, 2, 2, 3, 3. So, she gets her spells from spirits, must be pacifist, will forget spells when thing go wrong, has a medium-sized spell list, casts with Charisma, and has some spell slots. Obviously some kind of Spirit-courtier, an Old, benevolent Witch, or a Shugenja from older editions.

Change a single roll - say, if her taboo was that she must perform sacrifice - and you've got an evil priest, possibly clad in heavy armor and using a two-handed weapon.

Of course, you don't need to create entirely new classes to play with this - just tweak the existing ones.

Cultist = Intelligence-based Warlock.
Reality Bender = Wisdom-based Sorcerer.
Shaman = Charisma-based druid.
White Mage = Intelligence-based Cleric.

(Just remember my thoughts on Wisdom, as mentioned above).

And so on. But abilities aren't the only thing you have to change - the source of power (which is mostly fluff anyway) can be changed at will. A cleric without a deity, for example, is not difficult to do.

Here is one example from a real campaign I run a while ago:

Mad scientist Iron-man Kobold. This character created himself a magi-tech armor that was pretty much part of his body; he didn't "learn" new spells, but improved his armor to be more powerful and versatile. Unfortunately, the amor would "malfunction" from time to time, with odd consequences. In practice, this was just a Intelligence-based Wild Sorcerer, remade to fit the player's ideas.

What's the point?

More options are usually nice, specially when you do not have to increase complexity to get it - you are not adding any new pieces to the mix, just playing with the ones you already have.

Better weapons through crits: fast, unbalanced, and brutal (5e)

After writing this post, I've noticed I am repeating myself on some subjects. The reason is that I'm writing a Manual of Arms for 5e, so I'm constantly thinking about these matters. Thought it might be interesting anyway, but if you're not into my 5e weapon musings, skip this one.

I've said this multiple times already but: the 5e weapon list is idiosyncratic (some decisions don't make sense), unbalanced (some weapons are obviously better than others), and a bit boring (some weapons are just too similar to one another).

The main offenders, as seem in the link above, are the mace, the morningstar, the trident and the greatclub. There are other bad weapons (pike, glaive/halberd, etc), but lets focus on the worst four.

While it isn't hard to fix these weapons, it is not easy to different weapons without adding new weapon properties. But that would necessarily make the game a bit more complex, and combat could get slower.

Critical hits are also a bit samey and boring in 5e: just roll some extra dice regardless of weapon. 3e at least tried to differentiate them (despite the ridiculous "confiming crits"). 4e was faster, with a result not dissimilar to 5e: maximum damage. It also had different weapon properties. 1e did "weapon versus armor", good idea but bad implementation. The RC had a whole Weapon Proficiency system. And so on.

In 5e, as you know, weapons are not really distinct or interesting unless you pick the right feat; then you can charge, power attack, stop movement, etc.

It seems that altering critical hits is the easy way to differentiate weapons. It doesn't affect combat in most rolls, and when it does, it does so in an exciting way. I touched on the subject here.

A decent critical hit table could solve things. However, I have somewhat bad memories of the endless tables from my Rolemaster games (and good ones too - I just disliked the endless rolling every turn).

Instead, just give a few different criticals to go with each type of weapon.

Versatile morningstar in Dark Souls. - source.

Let's start with fixing the for main offenders: what do they have in common? Well, all those weapons seem to be... a bit clumsy? Maybe the reason they are worse is because they are farming/fishing implements used as weapons. Which, for many readers, might be reason enough to keep things as they are. I just think these weapons look cool and I want them to be useful!

GURPS would call most of these weapons "unbalanced"; weapons that, unlike a sword or quarterstaff, have one side that is significantly heavier than the other, and might be slower because of that (but, in GURPS, they often deal more damage).

One option is giving them extra damage on crits. I call this property "Brutal" to go with the barbarian. Maybe something like "on a critical hit, the first damage die die you roll deals maximum damage (for example, 6 on 1d6) regardless of the result".

[another option would be just giving all these weapons +1 damage. Yes, the mace would do 1d6+1 damage, worse than 1d8 because of crits, but still a lot better than 1d6. Seems like a missed opportunity for 5e that no weapon works this way, but 1d6+1 in a table full of 1d4/1d6/1d8/1d10/1d12 does look ugly... of course, 2d6 also looks ugly and is in 5e for no decent reason. But I digress.].

You could probably create an interesting property to all Unbalanced weapons, not only these four. Maybe adding the weapons weight (maximum 8 or 10) to damage, as I suggested before. Makes the greataxe a bit better.

How about Fast weapons? Weapon speed usually make games a lot more complex, but it wouldn't be much of a problem if it only matters on crits. In 5e, the only weapons that are actually "faster" are light weapons - a rapier is no faster than a maul, since the number of attacks remains unchanged.

To make a weapon fast in 5e we could take a page form my Dark Fantasy Basic and give it one extra attack on a crit. Or use something similar to the Great Weapon Master feat, allowing one attack with a bonus action... or give it advantage if you already can attack with you BA.

And, as I've said before, all these things tend to make heavier weapons (and specially unbalanced ones) good against heavier armor, since the higher the opponents' AC is, the greater the chance that this extra attack will miss.

You could even create a continuum between Unbalanced and Fast - dagger on one extreme, maul on the other, with longsword close to dagger and greataxe close to maul... While this looks complicated, it wouldn't be hard to implement with a single digit. Say, "Unbalanced (5)" means it can add 5 points of damage on a crit, but it would take a -5 penalty when you make an attack using a bonus action... Or maybe -5 penalty to you next attack, unless you use a bonus action to balance the weapon. Or go the opposite way and have a single Balanced property that would allow you to get a bonus when attacking with a bonus action.

Bonus points if you mesh this with scaling weapons... Finesse weapons would be faster, heavy weapons would be slower. Although using weight takes care of the issue: dexterity weapons are usually lighter anyway (except for the heavy crossbow etc.).

Being a fan of elegance in game design, I'm very tempted to solve all these issues with a single keyword, of course, instead of adding more and more mechanics.

It's certainly doable, but I'm not sure how desirable. I mean, there are multiple solutions - but since WotC didn't bother, I'm afraid most fans may ignore it as well.

Sigh. Well, what can I do? I just like medieval weapons.

Moon-headed Giant

(For an idea by Eric Nieudan)

Armour class: as plate
Hit dice: 8
Move: normal
Attacks: 2x meteoric sword (1d8+1/1d8+1) or other +1 weapon.
No. Appearing: 1
Morale: 9
Treasure: 10,000 SP plus meteoric weapon
Alignment: mostly Chaotic.

Moon-headed giants were once satellites to a forgotten planet that orbited the Black Sun. For the first time in a millions of years, they aligned enough to anti-eclipse the Black Sun for a couple of seconds, and give a small respite to the miserable creatures that inhabited the planet.

It was enough.

The evil star cursed the five moons to live as deformed giants in a far away planet, never to return to the dark skies they used to call home.

Now banned from their original system, these lunatic giants are plagued by bouts of depression, alternated with maniac phases. They often try to conquer or build empty castles so they can rule over nothingness as if it where the dark skies they lived in the past.

They display a keen interest on silver, rare minerals and inanimate matter from outside their current planet, and wield +1 meteoric weapons of their own making. They hate the bright sun almost as much as they hate the Black one and prefer to dwell in the dark, sometimes venturing out during the night.

Fairly intelligent but unstable and mostly disinterested in human affairs, they can be reasoned or bargained with until they get bored or angry - although each Moon-headed Giant (Blood Moon, Gold Moon, Broken Moon, Bad Moon and Cold Moon) has its own distinct personality, not always compatible with the others.

This monster is released under a CC-BY license (https://creativecommons.org/licenses/by/4.0/).