I was asked recently about monster stat blocks and how I come up with them. I thought we should take a brief tour of the anatomy of a Vaarn monster, dig around in their metaphorical guts, and learn what all their numbers and stats are telling us. Hopefully you will arrive at a clearer understanding of why I stat things the way I do, and have a simple checklist that you can employ yourself if you want to make your own Vaarn monsters.


All monsters have a name, which is the first part of their stat block a reader encounters. I want to focus more on the mechanical side of the stat block than the conceptual, but I do advise that you attempt to capture something of the creature’s nature via their name. I like to go as simple as possible while still being evocative. If the creature sucks the memories right out of your head, just call it a Memory Eater. If the creature is a snare of wires that tumbles across the desert, call it a Tumblesnare.

If you want to sound a bit fancier, I recommend giving the creature a Latin- or Greek-rooted name. Chromavore means, roughly, ‘colour eater’, and is a fun echo of carnivore. You can also go for extremely obscure or archaic words: the Yurlings, for instance, are named after an obscure Scots word for ‘a small person’.

Monster Type

Vaarn monsters have a listed type or category, to let the Referee know what sort of being they are. The currently extant categories are (in order of rarity):

  • Biological (this covers sentient beings, animals, and plants. Most Vaarnish monsters fall into this category)
  • Synthetic (anything with extensive cybernetic implants or an artificial brain)
  • Fungal (mycomorphs, basically)
  • Hypergeometric (a creature that exists outside of Euclidean space)
  • Psychic (anything with psychic powers. This has [so far] always been a secondary category, there are currently no official Vaarn monsters that are only categorised as Psychic)
  • Outsider (something that crept into our reality from elsewhere. A catch-all bucket for really weird creatures)
  • Mineral (living rocks; currently just Lithlings)

You can add your own categories if you like! They originally existed to settle questions about what was and wasn’t a robot, and have expanded from there. Some Exotica and other weapons specifically affect certain creature types differently, so be aware of that.


Previously known as Hit Dice (HD). A monster’s Level is a measure of two things: the monster’s HP pool, and its general power and competence. Let’s cover these one at a time.

A monster with a higher Level has more HP, and will stick around in combat longer. I think this is self-explanatory. What exactly the HP is supposed to represent is a matter of constant debate amongst OSR bloggers and I’m not interested in re-litigating it here. For me it’s ‘stay in the scene’ points, and when a monster runs out, it’s dead. Creatures with high HP are a more credible threat.

Monsters also add their Level to attacks they make, and use their Level as a stat bonus if they ever need to make a Save against something the PCs are doing to them. This is really important, because it means they basically have one single ‘do stuff’ stat, and are good or bad at making Saves dependent on that stat. So a Level 10 monster is orders of magnitude more competent and threatening than a Level 1 monster. Remember that they add their Level to attack rolls, so high Level creatures are better at attacking and dealing damage.

My general Level benchmarks look like this:

  • Level 0: a child / a small weak creature
  • Level 1: an average human / a dog-sized creature
  • Level 2: a well-trained human soldier / a wolf-sized creature
  • Level 5: a horse-sized beast / something that could attack and kill a well-trained, armed human.
  • Level 8: a monster that could kill many well-trained, armed humans.
  • Level 10 (or higher): an apex predator, a monster other monsters are afraid of.

You may notice that I haven’t defined every Level. This is partly because pegging a monster’s Level is more art than science. I can’t always define what makes one creature a Level 3 encounter and another a Level 4 encounter. My advice if you’re struggling is to put the monster at Level 5. If that seems too strong, move it down one Level and consider it again. If that seems too weak, move it up. You should also consider the relative Level of the PCs you intend to pit the creature against, and whether it is supposed to be intimidating or nearly harmless.

I tend to make swarmer-type monsters, that appear in large numbers, Level 0 or 1, because each individual is bolstered by its fellows. A swarm of Level 5 creatures is going to be a slog to fight. I’d also suggest that solo ‘boss’ monsters be Level 7 or 8 at least, as Vaarn PCs can put out a lot of damage with Gifts and generally you want a solo monster to survive the first round. Obviously if they nuke the boss then they nuke it, but there’s no reason to make the combat a foregone conclusion.


How difficult it is to meaningfully hurt the monster in combat. This is another survivability slider to play with. A Level 1 creature with high Armour will feel really different to fight than a Level 15 creature with low Armour. The first one hits you rarely with a +1 bonus, but is difficult to hit in return; the second will be hitting you constantly with a +15 bonus, but you’ll be hitting it constantly as well. Both creatures will stay in the fight for a while, but the two will feel very different to the players.

The scale for Armour look like this:

  • Armour 09: a goo or slime, minimal defence.
  • Armour 10: an unarmoured adult human.
  • Armour 12: light or leather armour.
  • Armour 14: moderate armour, equivalent to chain mail.
  • Armour 16: heavy armour, full medieval plate.
  • Armour 18: superheavy armour, equivalent to an old-tech powered fighting suit.
  • Armour 20 or higher: extraordinary / supernatural resilience to damage. Use sparingly.

The Armour score I use for monsters is driven partly by the fiction and partly by the role they could play in combat. Swarmer monsters are usually given Armour 12 or lower, while solo boss monsters usually rate 16 or higher. There is, again, no exact science here. If you’re unsure, start the creature off at Armour 15 and see if that needs lowering or raising.

I would be remiss not to point out that ‘Armour’ also covers extreme agility as well as physical protection, so sometimes an airborne or highly athletic creature will rate a high Armour score.


How brave is this creature? Morale works a bit differently in the Vaults of Vaarn rules than in vanilla Knave and other B/X derivatives, in that you’re not trying to roll under the score on 2d6 but rather add the Morale score to a d20 roll and beat 15. I did this so Morale would become a ten point scale, in line with most other attributes.

The Morale scale looks like this:

  • Always Flees: self-explanatory
  • Morale 1: cowardly, undisciplined.
  • Morale 5: a soldier of average bravery.
  • Morale 10: very confident, unlikely to flee.
  • Morale 15: will never flee.

Knowing what Morale to assign a creature is, again, a matter of art rather than science. Some are obvious: mindless drones will have super high Morale, cowardly ambushers will always flee if the fight turns against them. I usually give packs of wild animals slightly lower than 5 Morale, and apex predators 8 or higher. If you can’t think of anything, Morale 5 will do just fine.


Also known as ‘group size’ if you’re reading the Deluxe Edition. This tells the Referee how many of the creature the PCs can expect to encounter in the wilderness or roaming around a vault. Often this is determined by the type of creature I’m imagining. Some creatures, like jackals or baboons, obviously appear in packs. Others, like a bear or eagle-inspired monster, make sense appearing alone.

The Appearing scale looks like this:

  • 1: self explanatory.
  • d3: divide a d6 by 2. I don’t normally use this one.
  • d4
  • d6: the ‘average’ group size. Default to this for group monsters.
  • d8
  • d10: a large group.
  • d12
  • 2d6: very similar to d12, but won’t produce a solo creature and has a higher average.
  • 3d6: a swarmer monster, average encounter will be 11 of them.
  • d20: slightly higher ceiling than 3d6, but more variance.

Almost all monsters are either solo creatures, or appear in groups of d6-d8. I rarely use any other group size. When trying to gauge this stat, it’s worth imagining encountering the maximum possible group size and how that would play out. Encountering 6 Giant Azure Scorpions would be very dangerous, so they’re encountered as a d4 group (and even 3 or 4 of them is tough due to their multiple high-damage attacks).


How the monster fights. There are lots of things to consider here: action economy, damage, and special attacks. We’ll cover each in turn.

Action Economy

Vaults of Vaarn isn’t a lovingly detailed tactical combat game, but there are a few tactical considerations baked into the combat mechanics. The most significant is action economy, or how many combat actions each side can take per turn. The baseline is that each PC can move once, and make one other significant combat action. Therefore a group of 4 PCs can make 4 attempted attacks per turn.

By default, a monster makes one attack per turn as well. Unlike PCs, however, monsters can make multi-attacks. These are indicated via a “+” sign joining the two attacks. As a general rule, creatures that outrank the PCs in action economy are going to be much trickier to fight than those that do not. Dangerous solo monsters should usually have multi-attacks they can make use of, or they are likely to be outclassed in damage by a group of PCs. In contrast, I would be very cautious about giving multi-attacks to swarmer monsters, as they already outnumber the PCs and so have an advantage in action economy.


Standard attacks deal a die’s worth of damage on a hit. The damage scale I use is as follows:

  • d4: a weak attack, equivalent to a punch
  • d6: a dagger or light weapon. This is the baseline for average monster attacks.
  • d8: a sword or two-handed martial weapon
  • d10: a heavy weapon, one that requires significant strength to use
  • d12: a weapon that requires two warriors to operate, damage from a creature far exceeding human size
  • 2d6: a variant on d12, will produce higher average damage
  • 3d6: a very strong attack, equivalent to a vehicle-mounted chaingun or similar
  • d20: an attack with high damage potential but high variance. I’ve never given a monster d20 damage, but it might work for a dangerous, highly unpredictable blast or beam. Be aware this could one-shot PCs with low HP.

Some creatures deal ability damage rather than HP damage: when they hit, they reduce the target’s ability defence directly. Damage of this type is extremely dangerous, as it can rapidly impede the PC’s ability to fight, and takes a long time to heal. I would use attacks of this type sparingly, and rarely create a monster than can drain more than d8 from a PC’s ability defence score per hit.

Special Attacks

Anything a monster can do that’s different from just rolling for damage. The only limit here is your imagination: monsters could grab PCs and latch onto them for auto-damage, steal a particular item or rations of water, implant or steal memories, force a PC to move or take some other action, mind control a PC, or any other inconvenience you can devise.

I generally allow an appropriate ability save vs debuffs or detrimental effects, although there’s a school of thought that says monsters should just be able to do the nasty things they can do, as long as they’re telegraphed.


Finally we get to the ‘everything else’ category. This section contains a brief description of what the creature is and does, to help the Referee quickly envision it, and convey that information to their players. Evocative, punchy language is your friend here. Aim for two or three sentences.
This is also where I list any notable special abilities or resistances a creature has. Some of this is covered by the monster’s Type (see above), but certain creatures have resistances or weaknesses to a particular damage type. I tend to peg these as taking half damage or taking double damage from a certain source, as this is easy to remember and implement.

Writing special abilities could be a whole blog post in itself, but my general philosophy is that ‘always’ or ‘never’ are strong baselines. I prefer to give monsters distinct, immediate things they can do, rather than +2’s on damage in certain situations. Describe the ability in concise, natural language, and trust the Referee and players to interpret the phrasing to fit their game.

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