Skip to main content

Quick 5e to OSR conversion method

I've seen this question pop up time and time again in forums and similar websites: How do you convert 5e material into OSR games?

This applies mostly to monsters, foes, and other creatures that sometimes are hard to convert into older systems because of the concepts of AC (Armor Class) and HD (Hit Dice). Modern 5e foes use HP (Hit Points) as opposed to HD, and their AC is ascendant (which means that the higher the AC, the better). So, whenever you're playing a module, things go smoothly until you encounter your first enemy, and then you're lost because how do you transfer such a detailed enemy into a much simpler system, while ensuring you're keeping it relatively balanced? Well, here's one way how you can do it.


I'd like to share with you a very simple conversion system, that will allow you to convert 5e foes and other creatures to OSR games with a descending AC (such as Labyrinth Lord). This also works with other games such as Scarlet Heroes (more info at the bottom of this article).

First and foremost, you will need this conversion chart. To work with it, you'll be taking into account a 5e monster's AC and its Challenge Rating. These two elements will provide you with the two basic stats for a successful conversion.


Now, let's use an example to make things even clearer. We're going to convert a 5e Aarakocra to an OSR monster.

On the right are the necessary stats to work with an OSR monster. In this specific case, we're looking at a Boar from Labyrinth Lord. On the left is our 5e Aarakocra.

1 - No. Enc.: Because an Aarakocra is a humanoid-avian type of creature, they don't tend to spawn in groups by default; rather, the GM tells the players how many of them are around according to the adventure's needs. Therefore, the number of encounter foes is 1.

2 - Alignment: The aarakocra's alignment is neutral good. However, most OSR games only play with Lawful, Neutral or Chaotic. So, it'd be neutral.

3- Movement: For movement, the aarakocra has a speed of 20 ft while walking, and a speed of 50 ft. while flying. OSR games show the maximum movement speed while exploring the world (used when the creature is moving in a hex map during wilderness adventures) and in parentheses the maximum encounter speed when in a fight (used for traditional dungeon delving and combat movement). The exploration speed is triple the encounter speed. So, the aarakocra would have a 60' (20') movement and a movement of 150' (50') when flying.

4 - Armor Class: The AC of the aarakocra needs to be converted from 5e's ascending AC system, to OSR's descending AC system. We can see from the chart above that a 5e AC 12 equals AC 7 in OSR stats.

5 - Hit Dice: For the HD, we need to take the aarakocra's Challenge level (1/4) and find it's equivalent in the chart. Monsters with a challenge level of 1/4 have 1 HD total.

6 - Attacks: For the number of attacks we can have fun. We can see an aarakocra will attack with its talons, may perform a diving attack, and will also get to attack with a javelin. OSR games take all basic body attacks and combine them together into a single stat while keeping weapon attacks as an optional attack the monster may or may not perform. In other words, the monster may choose to attack with its body and basic skills, or may choose to use a weapon instead. In the case of the aarakocra, we can say it will perform 3 attacks in one turn, or use its weapon. Why 3 attacks? Because it will try to use its talons (it has 2 talons, so 2 attacks there), and it will try to fly and slam its opponent with a dive. Therefore, the aarakocra's attacks would be 3 (2 talons, dive attack) or 1 (weapon). Other types of body attacks monsters in OSR games tend to perform are: claw(s), bites, tail, breathe, horn(s), tentacle(s), constrict, fist(s), beak, rear claws, hook(s), mandibles, sting, roar, cold touch, hoove(s), head butt.

7 - Damage: For damage, we can focus on the simple dice rolls of each attack, ignoring all added bonuses. We want to keep it simple. The talons do 1d4 damage, and the dive attack deals 1d6. The javelin also deals 1d6. Therefore, the stats for damage would be: 1d4/1d4/1d6 (for the 2 talons, dive attack) or 1d6 (for the weapon attack).

8 - Save: Saving throws are calculated in OSR games by comparing the monster stats to that of a Fighter. Basically, the number of HD tells you the equivalent of a fighter's level. So, 1 HD = 1F (or a 1 level fighter). The chart of a fighter's saving throws is the following:


9 - Morale: For morale, you need to calculate how likely is the monster to flee in combat. The lower the number, the faster the monster will flee. To check for morale, you roll 2d6. If the number is higher than the monster's morale, the monster will flee. Therefore, monsters with a morale of 12 will never flee and will always fight to the death. The average morale level for most creatures is a 10, so we can assume an aarakocra has an average morale level due to its inherent training.

10 - Hoard Class: Hoard class corresponds to the type of treasure a monster will drop when slain. This may vary depending on the OSR system you're using. Most individual monsters drop no treasures, but you may choose to make them drop some depending on your needs. We can say that a single aarakocra will hold only copper pieces (CP), therefore being a I. The type of treasure dropped is represented by a roman numeral in the following chart:


11 - XP: After determining the type of treasure a monster will drop, comes the XP. This is connected to the number of HD a monster has. For this reason, monsters with more HD will give you more XP. Our aarakocra has only 1 HD, thus it will only give 10 XP. Maybe a champion aarakocra with 3 HD will give you more XP points than your average humanoid-avian. Check the chart below:

12 - Description: Last but not least comes the description of the creature. I'm not including any for this example, but you can easily find the description of an aarakocra online.

So, here is our converted aarakocra (next to the original 5e one):

And that's it! Now, if I wanted to include an aarakocra in my OSR game, I could! The stats are fully functional and have translated nicely from 5e to my old-school campaign.

In the case of a monster having specific spells or attacks, you can check if there's a Magic-User, Cleric, Druid, or Illusionist spell equivalent and use it. Or, you can convert them. The format for conversion is quite simple:

Name of spell
Level: #
Duration: # rounds/# turns (per level)/# days/Permanent/Instantaneous/See below
Range: # ft. per level/ # ft./Touch/See below/Self

Description of the spell. It generally is 1 to 3 paragraphs long, specifying any details, facts, or other requirements. 
Here's a fully converted Choldrith from 5e using this conversion method. As you can see, it's all about having fun.


Et voilà! I hope this is useful for your games and campaigns.

FOR SCARLET HEROES PLAYERS:
In case you're playing Scarlet Heroes, note that some monster stats are not needed, such as the Save value, the Hoard Class, and the XP value (see page 56 of the Scarlet Heroes book for more information). Monsters in this game do not need to save, but they do include a Skill Bonus trait. It will be a +1 for average monsters, +2 for skilled monsters, +3 for elite monsters, and maybe higher values for bosses and supernatural foes. For the Hoard Class, Scarlet Heroes uses the chart that's included on page 82 of the book. Instead of monster XP, Scarlet Heroes uses XP points that are awarded +1 per completed game session. This is better explained on page 22 of the book.




Comments

  1. Well done! Im gonna use this method to convert 5e monsters into Minimum (osr system) monsters.

    ReplyDelete
    Replies
    1. Thanks, Isperia! Let me know how it goes!

      Delete

Post a Comment

Popular posts from this blog

Customizing your Scarlet Heroes experience

You can tell I really like Scarlet Heroes because I'm always bringing it up. Not only was it the very first solo RPG book I bought, but also I find myself going back to it, time and time again, despite having other titles in my collection.   The illustrations of the book are also fantastic, in my opinion! Due to its origins (see my previous article for a quick overview on this), Scarlet Heroes is easily customizable and adaptable. This is exceptionally useful if you're playing entirely on your own.  By default, the game comes with the monsters, spells, and lore of the Red Tide , an original campaign setting by Kevin Crawford (the one man behind Sine Nomine Publishing), which was made available as a Labyrinth Lord supplement around the time Black Streams: Solo Heroes (Scarlet Heroes' predecessor) was originally released. The world of the Red Tide was inspired by Southeast Asian myths and culture. When the full Scarlet Heroes was released via Kickstarter, the Red Tide setti

Tools #1: Fate/Fudge dice Oracle System

This is an easy oracle system that can help you when playing solo, or when you're GMing an RPG session. All you need is a pair of Fate/Fudge dice. If you don't know what that is, keep on reading! Do you have any Fate/Fudge dice (Fd’s)? If not, you can easily create your own. All you need is: Some ordinary d6 or six-sided dice. A black sharpie or any other permanent marker. The following chart.  ----------------------------------------------------------------------  Source: https://boardgamegeek.com/image/726115/paolo-robino ----------------------------------------------------------------------  It’s a cheap and easy solution that works just like the real deal! ----------------------------------------------------------------------  My example. As you can see, it's a simple process. ----------------------------------------------------------------------  Now, with your Fd’s ready, here’s the Oracle. You just need 2Fd’s for it. The meanings wou