Dread Fury and d100 Combat

Happy the blest ages that knew not the dread fury of those devilish engines of artillery, whose inventor I am persuaded is in hell receiving the reward of his diabolical invention, by which he made it easy for a base and cowardly arm to take the life of a gallant gentleman; and that, when he knows not how or whence, in the height of the ardour and enthusiasm that fire and animate brave hearts, there should come some random bullet, discharged perhaps by one who fled in terror at the flash when he fired off his accursed machine, which in an instant puts an end to the projects and cuts off the life of one who deserved to live for ages to come.

Don Quixote by Miguel de Cervantes

Continuing my posts on building a d100 game system for an upcoming fantasy Renaissance campaign. The focus here is combat, and mundane weapons and armour (I will get to magic in a future post). Starting with a bit of combat philosophy, I will look at damage and how it is mitigated by active and passive defences, initiative, and actions in combat. I will end with my design choices so far.

What is Combat in Roleplaying Games Anyway?

There have been conflict resolution procedures in most roleplaying games, starting from the first edition of D&D. Because combat involves chance and opposing wills, its outcomes are uncertain, so combat can take the game in unexpected directions. Which is part of playing to find out what happens.

One framing for combat in roleplaying games is Combat as Sport versus Combat as War, where combat as sport might be a “fair fight”, and combat as war has a much more adversarial relationship between players and GM, where all sides seek asymmetric advantages to win at minimal cost (just as you would in the real world). I will add another axis to this, labeling one end of this axis “Combat as Fail State”, and the other end “Combat as Speed Bump”. Speed Bump combat is a combat that you power through in as few dice rolls as possible – maybe only one roll, in order to get back to whatever the game is focused on. Combat as fail state means that gameplay seeks to avoid combat at all costs, as the risk of character mortality is so high.

A quick diagram and some contestable examples. The closer you are to the point where the X and Y axis overlap, the more time the game system devotes to combat as the default mode of play.

Different groups of players will have different preferences for what they want in combat. Different games or campaigns can also have different expectations set in session zero. For a Night’s Black Agent’s campaign, I promised my players boss fights, but I did not promise that they would survive them.

For a d100 renaissance game with gunpowder weapons, I think a key design consideration is how lethal firearms will be in the setting and rule system. On the whole I think that combat is an expected element in most d100 games, and they fall more at the realistic Combat as War side of the graph. This may be due to the early Runequest (RQ) combat rules being derived in part from the authors experience of medieval reenactment combat in the Society of Creative Anachronism. It is a lot harder to think of hit points (HP) as plot armour when the rules say your character took a critical hit to the head. So you get a more visceral feeling as you play, unlike in D&D where you can feel immune from consequences due to HP bloat.

Damage, Special Damage, and Wounds

I will compare and contrast a few different d100 games, splitting them up into chunks. These are of necessity, brief descriptions of rules that often detailed at length in game books, so many of the quirks and subtleties of each system will be glossed over:

• Runequest 2 (1978): A hit means you roll weapon damage, and hit location, then subtract a fixed number for armour worn in the location from the damage roll. A PC has both general hit points and location hit points. Wounds affect both general and location HP. When general HP drop to zero, the PC is dead. When a specific location reaches 0 HP a character falls (legs), loses use of limb (arm), or has two turns until they die (abdomen, chest, or head). A limb hit for six more points of damage in a single blow is amputated. While this is a bronze age fantasy game, it includes the comment “A modern, high velocity, bullet, hitting a limb hard enough to put it out of action, will probably kill the owner of the limb by hydrostatic shock.” (RQ2 p.20) A critical hit (a roll equal or less than 1/20 of skill) ignores armour, while an impaling hit (a roll equal or less than 1/5 of skill) increases damage (eg a weapon doing d6+1 damage would do 2d6+2 damage).
• Mythras (2016): Retains location HP, but drops general HP. Location HP are a bit higher than in RQ. When you drop below 0 HP in a location, Endurance checks are needed to avoid being disabled (limb) or incapacitated (head, chest, abdomen). The special effect menu has 40+ options you can choose from, but in my experience Choose Location, Bypass Armour, and Maximise Damage are selected 95% of the time by my players. Choose Location is a dominant strategy in special effect selection, as you can choose an already wounded location. This makes Mythras PCs more vulnerable to being quickly knocked out of combat than RQ PCs (an average PC has 4 HP in their arm, so four points of damage there is enough to trigger a karmic death spiral), unless the GM deliberately avoids hard moves against the PCs and has foes attacking in Combat as Sport mode.
• Call of Cthulhu 7E (2014): Retains general hit points, but drops location hit points. A single wound that does less than half HP just reduces your HP score. A wound that does more than max HP in one blow causes death. Anything in between is a major wound, the character falls, must make a CON check to remain conscious, and if reduced to 0 HP is dying. A dying character needs first aid to avoid death. CoC PCs rarely wear substantial armour. An extreme success on an attack causes increased damage. Pulp Cthulhu (2016) doubles HPs and does not have major wounds, but does check to see if they are knocked out if they lose half their HP in one blow.
• Clockwork and Chivalry 2E (2013): Similar to Coc7E, but you can keep fighting below 0 HP if you make a Resistance roll, until you reach negative HP equal to your starting HP score. This potentially doubles your HP, but with more uncertainty than Pulp Cthulhu. Major wounds are more specific than CoC7E, and are determined by rolling on a table, and range from cosmetic scars to temporary incapacity. Major wounds when below 0 HP roll on the Grievous Wound table, which can include instant death outcomes. Armour only provides half protection against guns up to their normal range, but full protection beyond that. Critical hits do maximum damage and ignore armour.
• Delta Green (2016): Damage bonus from STR is a fixed modifier (from -2 to +2) rather than a die. Has general HP and no location HP, and at 1 or 2 HP you are unconscious, at 0 HP you are dead. Any time you are reduced to 2 or fewer HP, you must make a CONx5 test to avoid losing 1d10 from a character stat. A distinctive feature of this game, is the lethality rating for automatic and heavy weapons, where weapons have a 10-30% chance of being instantly fatal if they hit, regardless of HP. If the lethality roll fails, add the dice together to determine HP damage. For example, a heavy sniper rifle has a 20% lethality rating, and where a Rifle does 1d12+2 damage (3-14), the sniper rifle will do 3-20 damage if it does not land a lethal blow.
• Mothership (2022): This game is not an evolution descended from RQ, and is a streamlined game focused on sci-fi horror (and a hefty does of “invisible rules” or assumed GM knowledge on how to run games). A character will have two wounds (three wounds if a combat specialist). Each wound has 10-20 health points. When you lose all of the HP for a wound, you roll on a wound table (different types of weapons have different tables). Armour is ablative, in that any penetrating blow destroys the armour. Armour ranges in value from 1 to 10. Weapons, however, can do anything from 1d10 damage for a Pistol, through to 1d100 damage for a Laser Cutter (which to be fair, is a one shot weapon with a one hour recharge), and some weapons inflict automatic wounds as well (such as 1d5 wounds for a frag grenade, which will kill most characters).
• Basic Roleplaying (2008): A toolkit system like Mythras, by default BRP uses general HP, a major wound system, and PCs stop fighting at 0 HP and take a fatal wound. BRP treats armour differently, by default armour is rolled randomly (the equipment tables retain an option for fixed armour values). This acknowledges that all armour has weak spots (typically at the arm pit, groin, or eye slot on a human), and creates a wider range of damage outcomes.

How many hits can an adventurer take and keep fighting? My own preference is that a PC should be able to survive at least two normal blows, so that they have time to change what they are doing.

Active Defence – Dodge, Parry, Block

One of the dynamic features of d100 games is that they include active defence options, as well as passive defence from armour (and in Mythras, shields). A PC usually has the option to parry with a weapon, to dodge a blow by movement, or to block with a shield. Parrying risks damage to the weapon, which can cause it to break. Dodge only works if the blow can be reasonably avoided – if you are stuck in place, or next to a cliff, or trying to dodge a house sized object, then dodge is unlikely to work. In Mythras, the equivalent to Dodge, Evasion, leaves you prone on the ground, which is only delaying the inevitable.

In CoC7E, you can fight back when attacked. If your roll is better than your foes, they take damage. You do not get bonus damage from extreme success when fighting back.

You have to go to a completely different game, Usagi Yojimbo, to find the classic defence mechanism of taking a few paces back out of range of the enemy.

The problem of shields

Compared to D&D, shields are amazing in d100 games. In RQ2, you could roll to block an attack with your shield, absorbing 8-16 points of damage depending on the size of the shield. One of the effects of increased protection from shields, is to increase the number of rolls between opponents in combat before a decision is reached, which increases the time required to play out a combat scene.

In Mythras for example, a heater shield blocks all damage on a location the shield is blocking, giving the shield. The difference between maille armour (six armour) and articulated plate (eight armour) is only two points. While this reinforces the dominance of the Choose Location effect (to avoid locations covered by the shield), it can make the Sunder effect useful to batter the shield down over several blows. A d10+2 Glaive with average damage of 7.5 a blow would break a six armour/12 HP heater shield in eight blows. In RQG, shields take 1 HP of damage each time a blow penetrates them, so it will take 12 blows to render a medium shield (12 HP) completely ineffective, but that first blow needs to do at least 13 damage.

The problem for a renaissance game, is that in history shields were abandoned as the quality of steel for armour and weapons improved in Europe, and combatants equipped themselves with two-handed weapons.

One solution is to just say that gunpowder weapons ignore all shields. I also like the “Shields shall l be splintered” house rule (you sacrifice a shield to negate all damage from one attack), but that does not make sense for the renaissance buckler shield, which is entirely made of metal, and is more of an aggressive deflecting device than a passive blocker. A roleplaying solution is to just say that people have stopped using shields, so its not an option for PCs.

Passive Defence – Armour

Armour is generally treated as passive damage reduction in most of the d100 games I have examined. The renaissance was a period of incredible change in armour, with older styles being superseded by improved plate armour that was both thicker and made of softer metal in order to be proof against pistol and musket fire. As muskets improved, heavier muskets with larger powder charges could penetrate almost any armour, so even proof armour was mostly abandoned by the mid-17th century in Europe (the Polish Hussars being a notable exception).

Polish Winged Hussar

I am going to look at how three game systems represent the armour worn in the renaissance: Basic Roleplaying (BRP), Mythras, and Clockwork and Chivalry (C&C).

• BRP: Full Plate grants 1d10 Armour Points (AP) or 8 AP in a fixed AP game. Half Plate grants 1d8 AP, or 7 AP. A heavy helmet would add +2 AP. While its not exactly on the list, I think a leather buff coat with lobstertail helmet and a metal breastplate, could be treated could be treated as Hard Leather with a Heavy Helmet for 1d6+2 AP or 4 AP.
• Mythras: Articulated Plate provides 8 AP. Half Plate is 5 AP. A combination of buff coat and plate armour is 3 AP in areas only protected by the buff coat (arms) or leather boots, 8 AP in the head and torso.
• C&C: Full plate grants 5 AP. Half Plate grants 4 AP, and Medium armour (buff coat, breastplate, and lobstertail) grants 3 AP.

Weapons

The Renaissance is also a time of change in weapons – if there was ever an era for a Gygaxian polearm list on the equipment chart, its the Renaissance! Its a feature of the game, rather than a medieval stasis bug, and of course, in a fantasy Renaissance you can make some decisions to mix anachronisms together. There were, however, compelling reasons to adopt gunpowder firearms over traditional longbows and crossbows:

• Muskets were cheaper than military crossbows, which were complex machines
• Deadly wounds could be inflicted at long range against opponents in the best armour
• Logistics was easier – shot can be quickly made in the field and is lighter to carry than arrows
• In siege or urban warfare, a firearm user does not need to expose themselves to return fire
• Less strength or fitness was needed to use a musket
• Materials for muskets and shot were not in short supply (unlike Yew trees in England)
• People preferred shooting them.

One feature of older d100 games, is that the difficulty to learn a weapon was in part handled by requiring a minimum STR and DEX score, eg in BRP a longbow requires STR 11 and DEX 9 to use effectively – in history it was noted that longbows required years of training, constant practice to maintain skill, and good physical condition to loose volleys of arrows in battle (and after a long campaign archer strength might be debilitated by disease). This could be reflected in base skills of varying levels for different weapons. Overall I prefer the Mythras approach of calculating base skill levels (adding two ability scores together) as it generally results in higher minimum skills for PCs.

The transition away from “proof” armour that could stop musket balls, was driven by the physics making it easier to increase the power of muskets, but armour ran into weight limits of what could be worn even by fit, trained, professional soldiers.The problem is that if you just boost the raw damage of firearms, to ensure they penetrate armour, then in any situation where the PCs are not wearing armour, a hit from a firearm will kill them in one shot.

Keeping things simple, I am going to consider only three weapons across three game systems: Basic Roleplaying (BRP), Mythras Firearms Supplement (Mythras), and Clockwork and Chivalry (C&C). The weapons of comparison are the rapier, the flintlock pistol, and the flintlock musket. Remember that weapon damage interacts with character HP, and armour, so while C&C weapons have more damage dice, C&C characters can fight at negative HP. This is very much an apples to oranges comparison.

Rapier

• BRP: 1d6+1+damage bonus damage, base skill 15%, 15 HP for parrying, STR 7 DEX 13 minimum to use.
• Mythras: 1d8 + damage bonus damage, base skill STR+DEX, 5 AP and 8 HP for parrying.
• C&C: 1d8 + damage bonus damage, STR 7 DEX 13 minimum to use.

Flint Lock Pistol

• BRP: 1d6+1 damage, base skill of 20%, one attack every 4 rounds, range of 10, STR 7 DEX 5 minimum to use, and malfunctions on 95-00. The value of primitive/ancient armour is halved against firearms (round up).
• Mythras: 1d8 damage, base skill STR+DEX, four actions to reload (less one with Rapid Reload combat effect, but with a typical PC having three actions you get a faster rate of fire per five second combat round than the other two game systems), range 10/20/50, ignores four points of armour.
• C&C: 1d6+2 damage, Range 5m, 3 rounds to load, STR 9 DEX 7 minimum to use

Flintlock Dueling Pistol (bonus weapon because C&C has a lot of firearms)

• C&C: 2d4+1 damage, range 10m, 2 rounds to load, STR 9 DEX 9 minimum to use.

Flintlock Musket

• BRP: 1d10+4 damage (1d8 as a club), base skill of 25%, one attack every 4 rounds, range of 60, STR 9 DEX 5 minimum to use, and malfunctions on 95-00. The value of primitive/ancient armour is halved against firearms (round up).
• Mythras: 1d10 damage (2d6 as a club), base skill STR+DEX, four actions to reload (less one with Rapid Reload combat effect, but with a typical PC having three actions you get a faster rate of fire per five second combat round than the other systems here), range 15/100/200, ignores five points of armour.
• C&C: 2d8+1 damage (d6 as a club), range 30m, 4 rounds to load, STR 11 DEX 9 minimum to use.

The Apples to Oranges Comparison

So let us compare weapons to armour, against typical HP for a normal (average damage) and a special success (maximum damage), in each system. Assumptions include average HP based on CON 11 and SIZ 13, no melee damage modifier. There are no buffs to attack or defence from magic, nor any use of luck mechanics.

Interpreting the box colours: Green (no damage), Yellow (damaged, but no chance of being knocked out of the fight), Orange (some chance of being knocked out of the fight), Red (almost certainly knocked out of the fight).

BRP Assumption: average armour rolls with heavy helmets (+2).

Assumption: first special effect is choose location Arm, which has 4 HP, second effect for a critical success is either Maximize Damage or Bypass Armour.

Assumption: weapons are at normal range for armour penetration (ie armour is halved).

Now after the gunpowder weapons have been fired, I will look at what the second blow does, with the following assumptions: (1) Pistol switches to Rapier, (2) Musket switches to two-handed club, and (3) the first hit was an ordinary success doing median damage.

The first number is the damage from the first blow, the second number is the damage from the second blow.

Some observations:

• BRP is the most lethal system for the first blow, as its special success results for double damage occur 20% of the time.
• C&C is the least lethal system for the second blow, in part because the Musket does such low damage as a club (d6 compared to 2d6 in Mythras).
• Mythras is the most lethal system for the second strike due to the cumulative impact of injury to a specific location. While it looks like full plate armour can entirely prevent a lethal first strike, if you chose not to go with Choose Location as your first critical success effect, and went with Bypass Armour and Maximize damage, then a pistol hit against an arm knocks a foe out, as does a musket hit against an arm, leg or head location.

Ultimately, I am not happy with any of these three systems. All three are a bit too dangerous to PCs who are expected to fight, and I think my group wants a long term campaign that is closer to “combat as sport” where they do not have to obsess about ensuring min/max combat and survival skills for their PCs. I think my main solution is to go with a general HP/serious wound approach, dropping hit locations, and to then buff HP to a range where all PCs will have 20-30 HP (which also ties in with the desire to use The One Ring journey and fatigue system). A high CON score still remains useful for mitigating serious wounds. I might use a Mothership approach, where gunpowder weapons inflict an automatic serious wound if any damage penetrates the armour, even just 1 HP. Another armour penetration mechanic not used by any of these systems, is the all-or-nothing approach, i.e. any firearm shot that penetrates armour inflicts full damage, with no reduction.

Initiative and the OODA Loop

For an online age, speed of resolution of actions becomes more important, because everything takes longer to resolve online. This is a reason for dumping the Mythras combat effects, or RQ strike ranks, and going for a set process when special or critical hits are scored.

The players want a swashbuckling game, which means the game system needs to allow creative exploits that are dependent on the situation and the environment. Rather than specifying all of these in detail ahead of time, I assume that as an experienced GM I can make judgements as the game progresses, offering fail forward or success with a complication where needed.

While I do find the Fast/Slow initiative/action system in Shadows of the Demon Lord interesting, my key decision here, is to adopt a Dr Who initiative system:

1. Intent – players choose their actions.
2. Talking actions are resolved first – even if its just witty repartee, and not a social skill check.
3. Running moves – this can include the party agreeing to a campaign loss in order to flee the combat with their wounded comrades.
4. Doing moves are resolved – this can include swashbuckling moves, operating machinery, opening or closing doors, or using a utility item such as an alchemical potion.
5. Combat – anything involving attacks and damage is resolved last (eg firing an artillery piece is a combat move, not a Doing move).

If it is not clear from the established narrative who should act first, resolve actions in DEX+INT order.

How Many Actions per Round?

Assuming the five second timescale of most d100 games, my preference is one attack action per player turn, per round of turns, unless some special resource is expended, or PC skills are over 100%. I am not planing on including magic that allows “haste” or multiple actions. The Dr Who system has a stacking penalty for multiple actions and I will have to think about how that plays out in d100 (a -20% cumulative penalty feels okay). Because of the way CoC7E opposed skills work, PCs getting to split their skill for multiple attacks will be rare until they get their skill up to 200%.

Other Design Choices

Fire magic and gunpowder do not play well together. Allowing mages with fire spells to trigger explosions in gunpowder weapons or powder magazines is fun and exciting the first time it happens, and dull as ditch water once it becomes an “I Win” button for all future combat encounters. So the first rule of magic in a game with gunpowder is that no one has fire magic.

After that decision, I think the fundamental call for an era of online play, where three hour sessions have become the norm for my group rather than four hour sessions, is how much time do I want to spend on combat? I think that both the micro-management of Mythras, and attack/dodge/parry/block of RQ, are simply going to eat too much game time. So something closer to the opposed check and fight back mechanics of Call of Cthulhu fits better – and the fight back can be described as the ripostes and counter-strikes of rapier play.

For dual wield weapons, borrow from 13th Age and have the secondary weapon hit on rolls of 2, but also fumble on a roll of 22 as well as 99 and 00. (so 12, 27, 92, etc are all hits if under the general skill level required). This includes shield bash. I will figure out how to handle bucklers when I build the equipment list.

Armour will be fixed values (because its faster than making AP rolls), with the best plate armour having a maximum of seven AP (so a d8 damage weapon can hope to do some damage). Armour imposes no penalties to skill use, except through the fatigue system.

Use CoC7E success levels, so an Extreme success (one fifth of base chance) inflicts increased damage, while a Critical success (01% chance) ignores armour. I am still thinking about the increased damage. Just maximum damage on one die will be plenty if its combined with the armour penetration rule below.

Gunpowder lethality will be represented by having any penetration cause a serious wound. For non-gunpowder weapons, I will do a pass for damage consistency, eg one-handed martial weapons should all do d8 damage, and not have a spread between d6 and d10. I will have to sit down for an afternoon with the weapon and armour tables I build, plus expected PC HP levels, and do a few white box combat tests. Part of session zero will be getting the players do some PvP with their character builds to see how it all works.

Building a d100 Roleplaying Game

Changed the blog theme for the first time in about a decade. I need to figure out a better widget for displaying a menu of past posts.

This post is the first of several on the topic of building a d100 roleplaying game for use in a campaign I plan to run. The design process is one where I take different bits of rules from different d100 games that I like, and stitch them together into what is hopefully a coherent design for maximum game fun at my table. This is me working through my preferences from existing games, plus my judgment about what will work for my established group of players, rather than me trying to design a new d100 game engine from scratch.

First, my reasons not to just run with a published d100 game that I already own:

• Warhammer Fantasy Roleplay 4th Edition: A bit too tied to the setting, and I am not convinced the core combat/magic rules are robust enough without buying a couple of expansion sets.
• Zweihander: Too fiddly, too pretentious, and I’m still annoyed at how much the author spammed their work on the roleplaying forums I read (before he was perma-banned).
• Basic Roleplaying System Reference Document: Too limited and bare bones in detail – it looks a lot like it was published to prevent any kind of retro-clone OSR flowering in d100 that might get too close to Chaosium IP. Not that this stopped…
• Cthulhu Eternal Open Game License: While I am not planning a jazz age horror game, there are some good ideas in here.
• Elric!: I probably ran into random armour points for the first time in this game, which I think is a good way to deal with the players wanting to stack every single bit of armour they can find (which leads to an arms race with GM adversaries to keep combat interesting).
• Flashing Blades: not a d100 game, but I would be silly not to take a look at the first game to focus on this swashbuckling era. I think I have the ubiquity engine’s One for All lying around somewhere too. 7th Sea 2E is too much of a narrative game to be useful.
• Basic Roleplaying: the big gold book is packed full of tools for building your own d100 games. Lots of different mechanics to mine here, even though its overall presentation is a little dated compared to the new toolkit systems on the block. The Blood Tide setting could be worth picking up for some piracy and nautical rules.
• Mythras: my group played this in its Runequest 6 edition, and while there is a lot to like in the game, my group never wants to play with its action point system or menu of 50+ combat special effects again. The Fioracitta setting could be worth picking up for ideas.
• Revolution 100: another system full of interesting ideas, but I find the text presentation of these ideas hard to parse in places, and ultimately the skill list is too truncated for the kind of game I want to run, and that my players want to play. Its take on extended conflicts is best in class.
• Runequest: The second edition was one of my first roleplaying games, and I will love it forever. The current Runequest in Gorantha edition is wonderful, but a bit fiddly around the edges. I really don’t fancy running its complex Strike Rank system online. I prefer its take on passions – with risk when you invoke them – to the “Mother may I?” bonus seeking of Mythras.
• Clockwork and Chivalry: while it is a renaissance setting that my players want, I am not keen on always evil witches, witch hunting, and religious violence, which look like core elements of this setting.
• Mothership: the new hotness of indie gaming with a fresh take on d100 games. If I wanted to run a short 8-12 session campaign, I would be using this as the base game engine, even though the original game is focused on space horror.
• Call of Cthulhu 7th Edition: The latest evolution of d100 from Chaosium – in some ways showing what could have been with the latest edition of Runequest if they had not tacked backwards towards the 2nd edition for reverse compatibility. Pulp Cthulhu also has useful ideas to borrow for a swashbuckling game.

Cover of the “Big Gold Book” from Chaosium

I also plan to borrow a few mechanics from non-d100 games, which I will discuss in the relevant sections. Rather than try and cover everything in one epic blog post, it makes sense to break it down into shorter posts. In the rest of this post I will write about character ability scores (aka attributes or characteristics – I use ability because it is a shorter word), and in the next post I will discuss skills.

The Eight Ability Scores

Where D&D uses the six ability scores of Strength (STR), Constitution (CON), Dexterity (DEX), Intelligence (INT), Wisdom (WIS), and Charisma (CHA), the d100 family of games usually has eight ability scores of STR, CON, DEX, Size (SIZ), INT, Power (POW), Education (EDU), and either CHA or Appearance (APP). POW is not a replacement for WIS, and represents aptitude for magic, psychic, or other super powers, plus Sanity (SAN) in Call of Cthulhu.

Ability Score Scale

Most d100 games follow D&D and have a 3-18 scale for most of the ability scores for human characters. The exceptions being INT and SIZ with a 8-18 range. Call of Cthulhu 7E adjusts these scores into a d100 scale by multiplying them by five.

In most cases higher scores are always better, the exception being SIZ, where being small could boost stealth, allow you to squeeze through a narrow gap, or hide inside a small space.

Random or Point Buy

The traditional random rolls for ability scores are 2d6+6 for INT and SIZ, and 3d6 for the other six ability scores. So “mean norm the average ranger” will have 13s for INT and SIZ, and 10s or 11s for the other six ability scores. Elric! (1993) is a more high power system, all eight ability scores are rolled 2d6+6. Non-human PCs can have different scores, eg in Runequest 2, a Great Troll would roll 4d6+12 for STR, but only 2d6+2 for INT.

Some d100 games allowed you to shift up to three points around between your scores. In my Tarantium campaign I allowed a player to discard one die and reroll it, a maximum of three times when generating all eight ability scores.

Mythras has a point buy system. The default is 80 points, which gets you average scores of 10 in your eight ability scores, but allows you to min/max as you see fit within the constraint that INT and SIZ require minimum scores of 8. In my Tarantium campaign I increased the point buy to 84 points.

Philosophically, random rolls mean you get to discover the character you will play, while point buy lets you choose the character you want to play. For long campaigns my preference leans towards point buy. In Tarantium I let my players choose. One rolled, the other four went with point buy. For point buy systems, it is important for the GM to point out break points for derived characteristics, to avoid system mastery traps in character generation (eg, building a Mythras character with only two action points).

For a high power campaign, I might use a variation on Rafu’s matrix method, which mixes elements of choice and randomness. This has a three step process:

1. Assign the numbers 1-8, each to one of the eight ability scores.
2. Roll a pool of 8d8. From the pool, assign one die roll to each of the eight ability scores.
3. Roll 1d8, in strict order, for each ability score.

This changes the base ability range from 3-18 to 3-24, average of 13-14 (not too far off Elric!), but I am okay with PCs being special snowflakes. The original mechanic used d6s as it only had to generate six ability scores.

Progression

Ability scores in d100 games are sticky and hard to change, often requiring significant time and money to train up. SIZ is usually the hardest to change, POW the easiest as using magic successfully might allow a check to increase it. A character maximum is usually three points above the highest possible rolled ability score, so for a 3d6 score, that is 21. In some d100 games injuries can permanently reduce an ability score.

In Tarantium I sometimes awarded increases by GM fiat, to represent training that the party got from their employers.

Derived characteristics

This is one of the areas where the different d100 game engines have significant points of difference.

• Hit Points: these are “meat points” not “plot armour”, and are usually calculated on CON and SIZ, divided by 2. In Call of Cthulhu 7E, its divided by 10 or by 5 in Pulp Cthulhu. D100 games can have a mix of general HP and location specific HP. Mythras only has location HP. Average general HP is around 12, or 24 in Pulp Cthulhu.
• Action Points: a Mythras score, based on INT and DEX.
• Damage Modifier: a bonus to melee damage, based on SIZ and STR, usually represented by rolling a an extra die that is not the same as your weapon die (which I find a little clunky).
• Spirit Combat Damage: a bonus to damage when fighting spirits. Based on POW and CHA.
• Movement Rate: a critical score in Call of Cthulhu, where flight is often a better choice than fight.
• Experience Modifier: In Mythras your CHA score can adjust the number of XP you get each game session. In Runequest the skills category modifier also adjusts experience checks.
• Healing Rate: In Mythras and Runequest your CON score determines how quickly you recover lost HP, typically 1-3 HP per day.
• Luck Points: A player resource to nudge die rolls in their favour. In Call of Cthulhu 7E these are generated randomly. In Mythras it depends on your POW score.
• Magic Points: Fuel for spells, usually determined by POW. Magic Point recovery depends on how magic rich your campaign world is. In magic rich Runequest you regain 25% of MP every six hours. In magic-poor Tarantium, you regenerated 1 MP per day in a flying city, and 0 per day on the ground.
• Strike Rank: Combat initiative. In Mythras its derived from DEX and INT, with a penalty for encumbering armour. In Runequest its based on DEX and SIZ, plus a modifier based on the weapon you are using.
• Sanity: In Call of Cthulhu, your resilience in the face of cosmic horror. Based on POW x5. In my Tarantium campaign I used Areté (moral excellence) to represent moral corruption in a manner similar to SAN. I am not fond of the actual forms of madness that older editions of Call of Cthulhu inflicted on investigators, which were derived from older stereotypes of mental illness.
• Encumbrance Points: no one likes encumbrance and fatigue mechanics, but in Runequest it is based on STR+SIZ, in Mythras its STR x2.
• Skills category modifier: In Runequest modifiers to skills are based on a range of ability scores, eg Agility is derived from STR, SIZ, DEX, and POW, while Knowledge is derived from INT and POW. Usually a flat modifier of -5% to +15% to the base skill scores. Not needed in Mythras where base skill scores are determined by combining two ability scores or doubling one ability score (so a range of 6% to 36%).

Implications for Other Mechanics

High STR, CON, DEX, and SIZ scores make you good at combat. High INT and EDU scores make you a better skill monkey. High POW is needed to be good at magic. As is typical for older game engines, only APP/CHA play a major part in the social pillar of play.

Mythras makes you really consider your ability scores. There are no dump stats.

My Design Choices

First, I will use CHA rather than APP, as a personal preference.

Second, I will drop SIZ and replace it with Social Standing (SOC) and a heritage based Build score. By heritage I mean “race” in old game design language, and I want it to represent a nature/nurture/culture background choice for characters. Replacing SIZ with SOC will let me diversify base abilities for a number of skills away from CHA, INT, and EDU (which is a solid clue to how my pans for skills are shaping up).

Third, I will go with the d100 scale ability scores of Call of Cthulhu, rather than the 3d6 range. This will let me use the same experience based improvement system for improving both skills and ability scores. As to whether or not I go with point buy, or that 3d8 OSR mechanic, I will talk with my players first. 3d8 x4 will give a number broadly comparable to 3d6 x5 (with a median of 54 versus 52.5, and a range of 12-92 versus 15-90).

Fourth, Hit Points will be based on CON/5, STR/10, and DEX/10, which will give a level of HP equal to Pulp Cthulhu. I am leaning towards general HP only, no location HP, with a serious wound mechanic at 0 HP or loss of half HP in a single blow, or something like the stepped wound system in Mothership.

Fifth, Melee Damage Bonus will be based off STR and heritage build (75 for a human, non-human heritages may vary from 25 to 110). Options for implementation include the classic bonus die, a flat modifier, or stepping up the weapon damage die (ie d6 steps up to d8, then to d10).

Sixth, Movement Rate will be based off DEX and heritage build (as above). I mostly run theater of mind games, but if its needed for chase scenes its good to have it.

Other mechanical decisions will need to wait until I refine the campaign setting and expectations of play with my players. For example, I might make Luck Points only available to players who roll their ability scores randomly, while players who choose point buy get a different fate/destiny/free will mechanic to use.

Mothership Hack

Inspired by the Mothership sci-fi horror rpg, I have been thinking about how it might play in a more heroic tone for a science-fantasy game. While it is a d100 system, its quite different from the BRP engine, in that Stats are more important than skills. A skill is a bonus of 10-20% added to a Stat. Key to the arrangement of mechanics in Mothership, is that failed Stat and Save rolls give your character stress, and critical failures (a double roll above the Stat/Skill level, e.g. a 99) trigger rolls on the Panic table, which is full of dangerous complications.

When your typical chance of success on a roll is around 20-50%, players are encouraged to avoid making rolls by interacting with the fiction in a slow but steady way – which works fine until you get jumped by monsters. Stress is used for experience, as you reduce stress gained in adventures, you turn that into improved Stats, Saves, and Skills. So for those who take great risks and survive, there are also good rewards.

Stats

For this hack, I think five Stats are needed:

1. Speed (SPD): use this for tests involving perception, initiative, movement, and quick reactions.
2. Strength (STR): use this for tests involving brute force, endurance, ignorance, and intimidation.
3. Intellect (INT): is used for most skill tests in stressful circumstances unless another Stat is more compelling in the situation.
4. Psionic (PSI): used for tests involving psionic talents or “sufficiently advanced” technology. In a fantasy game I would call it Power (POW).
5. Warrior (WAR): used for combat tests and warfare (yes it could have been COM for combat, but COM makes me think of Comeliness in the old AD&D Unearthed Arcane. CON for conflict would also work, but is close to Constitution, perhaps BAT for battle as an alternative?).

For a non-horror game, I think the Stats should be higher than in Mothership, so I would let players assign Stat values of 20, 30, 40, 50, and 60. Mothership has Stats cap out at 85, so with the customisation options below, you do not want starting Stats higher than 60.

Saves

Mothership is not to different from BRP, except what might be Endurance and Dodge are merged into Body. Keeping with just three saves:

• Chaos: used to resist mental harm from psionic (or magic) attacks, and to perceive true reality. In Mothership this is called Sanity.
• Will: used to resist loss of control over your actions from situations involving fear, passion, and other emotion surges. In Mothership this is called Fear, but I think Will or Willpower covers a wider range of situations, especially if you want to insert Runequest or Mythras style passions for the PCs.
• Body: used to resist physical harm, including from disease or invasive organisms. Could also be called Thews if you want to lean into Sword & Sorcery genre.

Assign the scores of 20, 30, and 40 to Saves for a horror/pain level similar to Mothership, or fudge the numbers up 10 to 20 points for a more heroic tone.

Wounds, Mana, and Fate

Mothership uses both Wounds and Health for tracking physical harm, with each Wound having 10+1d10 Health, and most characters having two Wounds. Any time you lose enough Health to cross a Wound threshold, you roll on a Wound table for potentially painful complications.

For my hack, I want a bit more certainty around Health, so Health is determined by 10 + STR divided by 10 (round up) for each Wound point.

Mana is the pyschic or magical equivalent of Wounds, and Essence is the equivalent of Health. Unlike Health, you are burning Essence points to fuel any PSI talents that you are using.

When you burn a point of Mana off, you get complications like nose bleeds (minus Health), migraines (plus Stress), conditions that impose disadvantage on checks, or a permanent increase your minimum Stress score.

For my hack, Essence is equal to 10 + INT divided by 10 (round up) for each Mana point.

Fate is a heroic resource to keep PCs alive, and Luck is the equivalent of Health/Mana. You can spend Luck at any time to manipulate fortune before making a roll (e.g. spend a luck point for Advantage) or after a roll (spend luck points to nudge the die result).

When you tempt Fate, however, flip a coin. If it lands the way you call it, there is no effect. If not, you make a roll on the Doom chart of horrible fates for heroes. Perhaps you get cursed by the Gods, lose a few points off a Stat or Save, or have the GM draw a Major Arcana card from a tarot deck to interpret what happens next.

For my hack, Luck is equal to 10 + SPD divided by 10 (round up) for each Fate point.

Character Customisation

Keeping this really generic, although you could customise archetype packages for genre/setting. Each player can choose three of the options below for their character, but each option can only be selected once:

1. +5 to all Stats.
2. +20 to one Stat.
3. +10 to all Saves.
4. +25 to one Save.
5. +1 Wound.
6. +1 Mana.
7. +1 Fate.

Having specific trauma responses to stress and panic is a bit harder to make generic. I might cut them entirely for a heroic campaign, or build a unique one for each PC based on discussion with the player.

Skills

Not much to say here, as the skill list should be tailored to the genre and setting. Broad or apprentice level skills should be +10% to checks, defined or expert skills should be +15%, and specific or master skills should be +20%. Adding in some perks or stunts for Master skills is quite appropriate. Skills greater than 20% might make sense if you campaign is aiming for transhuman or demigod power levels.

So Militia Training is +10% to WAR checks, while Melee Weapons is +15%, and Long Spear is +20%. Perhaps your hero might acquire and learn to wield a Spear of Destiny at +25%.

For our science-fantasy game you might have Psionic Training at +10% to PSI checks, Telekinesis at +15% and Soul Blade at +20%. Perhaps you character learns alien secrets and learns to manifest the Dual Soul Blades at +25%.

Mythras or Call of Cthulhu have some good packages of skills, and while Mothership only hands out a few skills at the start, for a more heroic level of play I think you could give out more skills to starting PCs, e.g. two Master, two Expert, and four Trained skills.

Vices

I would be temped to take the list of Vices from Blades in the Dark and have players pick one for the PC to indulge in to reduce Stress in downtime actions.