Playing an Adventure

NOTICE: this is the most work-in-progress bit at present. It is entirely un-play-tested and likely wildly unbalanced. There may even be a few contradictions/conflicts of rules or procedures I haven't caught or dealt with yet! Expect changes! Including significant ones.

This document covers the rules needed to play the Octas Tabletop Role-Playing Game in its most simple form. It is intended to be the bare-essentials for getting the game going without excessive study or work. A companion document, Extended Rules, contains further rules and refinements which may improve the depth and detail of the game, but are not essential.

Beginning players are recommended to start with just these Basic Rules, until they are familiar with how to play. A good rule-of-thumb is: if the game is becoming a bit stale, it is time to start poking through the Extended Rules section for things that look like interesting additions to your game.

In the context of a TTRPG, an Adventure is a prepared setting with non-player-characters (NPCs) which the Player-Characters move around in and interact with. It provides a framework in which the group-story is set so that Players and GMs are not left groping in the dark for ideas on what to do. Adventures are, however, generally very open-ended and so the exact same adventure may lead to distinctly different stories with different players.

The Octas/fallen genre module comes with a very-simple prepared adventure: Outside the Gates which new players and GMs are encouraged to explore.

Playing the Game

The GM begins with full knowledge of the adventure while the players should begin with none. Then the GM begins describing the player's starting position in the story, and the players describe what they do next. The adventure module acts as a guideline in which the story is to take place and the players negotiate their way around the adventure with the GM using the module contents as a framework.

While playing an adventure, some tasks common to all adventures will be performed by players and the GM, the rules for which are outlined below.


As a role-playing game, it is important to role-play. Go figure!

The primary goal of this type of game, for the player, is not to amass huge amounts of imaginary treasure (though there is nothing wrong with that from the character's perspective), but to tell a story.

And it is a story that is told as a group. It is not the GM's story. It is not the players' story, or any one particular player's story, though a focus may naturally shift about from player to player and even the GM throughout the game session.

From the GM's side, this means that players should not be herded, or 'rail-roaded' to specific goals and events, although gently guiding them in a particular direction via incentives is usually not a bad idea.

From the players' perspective, it is still important to respect the GM's story framework, and not constantly try to actively thwart it. If the story requires the players to go down into the dark basement with one dodgy flashlight, and it is obvious to the players what is likely down there, that is fine: but is it obvious to the characters? It is also helpful if the GM has provided some reason for the characters to go down there against their own better judgement, of course.

This requires a level of suspension of disbelief to be enacted. From the player perspective, things like magic, hyper-advanced technology, monsters, talking animals, and so forth are a bit ridiculous, but you are telling the group story from the characters perspective, and in the world the character knows, such things may be mundane, or even fantastical but still very real.

It is important to take the character's perspective within the game. For example, if your character is exploring a dark and mysterious place with a hint of danger in the air, you the player knows it is just a story and a game, and you - the player - are in no real danger, but resist the temptation to make jokes about a particular threat, or even just outright ignore it in favour of discussing something entirely outside the game context with other players. Look from the character's perspective - where the danger and fear are real, and consequences potentially dire. It is respectful of the story, and the other people in your playing-group, if nothing else.

Which doesn't mean you can't make fun of the monsters or situations (though best not be mean about it to the GM!). After the session is appropriate, or even in-story, after the danger has passed, it is not unreasonable that some of the characters might make light of the passed danger as a way of coping with the stress and terror they just had to deal with.

So, you - or even your character - might make light of the fact that the axe-wielding maniac has watched far too many axe-murder horror movies themselves and become a walking cliche. But not at the time they are dodging the axe, which - cliche or not - is heavy and sharp.

The exception would be if it is the type of game where making such in-action wise-cracks is, by prior agreement of the group, appropriate: There is nothing wrong with playing the game as a farce, as long as everyone is in on it.

And the axe-wielding maniac can also be perfectly genre-aware and play to that too!

It may also sometimes be appropriate if the character themselves is a wise-arse, but they have to be consistent about it and still within the game's context. This can also be fun, but is actually quite hard work - professional comedians get paid while people telling jokes to their mates don't, for a reason.

Task Rolls

Whenever a character wishes to complete a task which has a chance of failure, they may be asked to perform a task roll.

For such a roll, one relevant Characteristic score is chosen (if more than one might reasonably apply, the player may choose which one) and any relevant skills, specialisations and favourites added to the number (and relevant weaknesses and dislikes subtracted). This gives a number which is the chance of success (CoS). Note that while this number will generally be between the 0 and 63 range of the dice, values outside of this range are valid.

The player then rolls DD dice and if the result rolled is equal or lower than the chance of success number, they succeed. If it is higher, they fail.

Additionally, a roll of 0-0 is always a success and likewise a roll of 7-7 is always a failure, irrespective of the CoS being rolled against. As such, if something is genuinely impossible or completely inevitable, it should not be rolled for.

Or the GM will have some 'splaing to do if the player rolls a forced success/failure!

Task rolls are not needed (and are recommended against) in any situation where there is no real penalty for failure - don't make the player roll the same task 15 times over until they finally succeed - that's just pointless. Task rolls are useful in situations where success or failure has consequences beyond just having to try again.

If the player has low chance of success but no repeat-penalty, it is probably better to just estimate how many times they are likely to have to try over and tell the players it took that many attempts and that much time to achieve. You may use an appropriate dice roll of your own choosing to randomise this time a bit if you like.

For tasks that are particularly easy or difficult, at the GM's discretion, the following modifiers may also be added to the CoS score to be rolled against:

Difficulty Modifier
Trivial +32
Easy +16
Simple +8
Normal 0
Challenging -8
Hard -16
Onerous -32

When a task roll contains a 0 or a 7 in the high dice, a skill-improvement (or weakness aggravation) may occur. See Improving skills, in the Character Creation volume.

Opposed Tasks.

These are where one character is pitting themselves against another (not just player characters, but non-player-characters played by the GM too). For example, two characters may try to use their Current-Physical ability directly against each other when struggling over the possession of an item; or a character trying to sneak past another might apply their Current-Physical ability (and any relevant silence bonuses/penalties) against their opponent's Current-Perceptual ability (with any appropriate detection-skill bonuses/penalties likewise).

Calculating rolls for opposed tasks is a little more involved!

For each of the two participants, add up their appropriate characteristics, skills and weaknesses for their side of the contest. They then subtract this from a DD roll each and whoever has the lower final result wins (if the numbers are equal, it is a draw and the GM can decide what this means).

Dice results (before the subtraction) with zero on high dice, give the winner - only - a skill-increase roll.

Likewise, for roll results with a 7 on the high dice, the loser - only - also gets a weakness-aggravation roll.

See Improving skills, in the Character Creation volume for more information on this.

If opposed tasks are used directly for combat (or any other situation where multiple skill-rolls related to a single event occur), only the final skill-check roll will invoke the chance of a skill/weakness-adjustment roll.


Combat in Octas tends to be fast and harmful. It is generally a thing to be avoided, in favour of other strategies, but all the same is sooner-or-later inevitable.

The mechanics of combat in the Octas game is deliberately somewhat simple, sacrificing both detail and realism for simpler game-play. This is to facilitate the role-play focus of the Octas rule set.

Some more sophisticated combat mechanics additions may find their way into the Extended Rules volume at some point, for use by players to whom such may appeal.

Combat may use the Opposed Tasks system, pitting the attacker's Current-Physical plus relevant skill bonuses and weakness penalties, against the defender's Current-Physical (which includes their ability to dodge/deflect attack) and their appropriate bonuses/penalties for that task.

This can, however, get a bit of a chore, as Opposed Task rolls are a bit mathematically involved and hence more suited for one-off rolls, while combat can involve several successive rolls for each player, so the combat system is somewhat streamlined for this.

You can also use the streamlined combat system for opposed tasks, if you are finding the opposed task system too tedious for a particularly repetitive event. The main difference is both parties get to make their own roll in an opposed-task, which can feel 'fairer' even if both systems are actually probabilstcally quite equivalent. The rule-of-fun is generally best applied here: When rolling dice is more fun, use opposed tasks, when it's a chore, use combat rolls.

Combat rolls start at a value of 32.

Then you add the attacker's primary characteristic (usually Current-Physical for melee attacks, Current-Mental for magical attacks, or Current-Perceptual for ranged-weapon attack) and all relevant bonuses and penalties (skills, weaknesses, favourites, etc.) in play.

Next you subtract the defender's defence primary characteristic (again usually Current-Physical for melee defence, Current-Mental for magical defence, or Current-Perceptual for trying to dodge) and all relevant bonuses/penalties in play.

Roll DD against this value and a score below the total is a hit, a score equal is a 'scrape' (apply half damage) and a score above is a miss.

Rather than re-calculate the whole tally every roll, keep sub-totals for each character handy and subtract (or add on rare occasions) on-going changes to these values as current-scores change. If a character switches weapon or mode of attack/defence significantly, you may still have to re-calculate their whole total-score, but due to the generally-quick nature of combat in Octas, this is hopefully not going to be too onerous.

Irrespective of scores, a DD roll 0-0 always hits, and 7-7 always misses.

A roll with a 0 in the high-dice, which is also a hit will gain the attacker a learning-experience roll.

A roll with a 7 in the high-dice, which is also a miss will likewise gain the defender a learning-experience roll.

Learning experience rolls should be performed immediately and any increases to skills/weaknesses are likewise applied immediately. As such, these are available in the very next usage of the relevant skill, even in the very next combat round! The GM should update any running-totals to reflect this.

Combat Damage.

If a hit is successful, then the attacker rolls the appropriate damage dice for their weapon and that damage is deducted from the appropriate ability score that the weapon effects.

If a combatant is wearing armour, then the armour may absorb some of the damage inflicted on them, as per that armour's description in the Armour section of the Equipment Manual.

Typically, any damage absorbed by armour damages it, and the damage must be repaired... or the armour replaced if it fails completely.

For example, Joan is attacking Ghol with a two-handed sword that does 2D+Phy of damage. Her Current-Physical attribute is 22, which gives her a Phy bonus of 2 (higher digit of her current Physical score). So each successful hit with her sword does 2D+2 damage. She rolls a 3 and a 6, so her damage is 3+6+2=11. Ghol is wearing armour that absorbs 1D of damage, and rolls a 4, so the armour takes 4 points of damage to itself, and Ghol takes the remaining 7 points to his Current Physical attribute.

If any Current score of a combatant drops below 0, then they become unconscious (or as good-as). Also, any remaining damage beyond that zero score is removed from the corresponding Base score as permanent damage! If any Base score drops below zero, the combatant is dead. For simplicity, non-recurring NPCs generally don't get the luxury of a Base score, they are dead when their Current score zeroes. Significant NPCs may, at the GM's discretion, use a base score in the same way as player characters. This can be useful when the aim is to subdue or neutralise a foe without killing them.

Attackers, generally, will preferentially attack still-conscious opponents, but if no-one is left to stop them, they may 'finish off' any unconscious survivors after the battle. Or they may take them captive, or just leave them and run off to tend to their own wounds, depending on their motivation.

Most animals will only kill an unconscious person if they actually intend to eat them, and intelligent beings might feel that taking them captive is more useful (or even just humane), so don't assume killing everyone left is going to be the norm. .... Except for the Re-lived (the undead of the Octas/Fantasy world) - leaving no survivors is part of their reproductive strategy!

While damage to temporary current scores can be rapidly regained with rest, medicine or magic, damage to base scores is permanent, so while a character getting that badly damaged may not be fatal, it will be very permanently detrimental! The damage-degrades-ability nature of Octas means players really should be getting worried as soon as their Current scores start to get down to about half-way, well before they start to risk unconsciousness and damage to Base scores.

Damage types.

There are four forms of damage that can occur, specified in the weapon/spell descriptions:

Physical damage is the most common type, and is dealt by most physical objects and energy-forms. It is applied to the Physical score. An explicit head-blow may re-allocate half of the damage to the Mental score, at the GM's discretion.

Mental damage is dealt by some magical attacks. Using magic oneself is the more common drain on the Mental score, though.

Perceptual damage is caused by attacks that target specific senses, such as blinding light or deafening sound.

Wilful damage is a bit more insidious, but attacks the actual will-power of the character.

Weapons and spells specify which characteristics they damage in their descriptions.

Clinging to life: If incoming damage to a Base score from a single strike is going to be enough to kill a character, the points of the damage should be re-distributed evenly across every Base score, with any remainder applied to the attacked Base score (if this results in a Current score being higher than the base score, it is not immediately effected, but will drift towards the new Base-score at the rate of 1 point per day, assuming nothing else knocks it down fist). The excuse for this is that, so close to death, any damage is going to permanently harm the character broadly. (Octas' role-play focus does try to keep characters alive, but there has to be a pretty serious penalty for getting them in this much trouble, all the same!)

For example: Jim is doing badly! He is unconscious, with his Temporary Physical zero and his Base Physical already down to 5 points, and he has just taken a blow causing 6 points of further Physical damage, which would definitely finish him off if applied normally. Instead, the Clinging to Life rule activates, and one point is deducted from every one of Jim's base scores, with the left-over two points being removed from his Physical score, leaving him with 2 points Base Strength. He has survived the combat round, and may yet survive the battle, but he is going to be maimed for life!

Jim made it in the end, but he has had to invest a lot in both skills-training and expensive equipment to compensate for his massively weakened condition, and the interest on the money he borrowed from that Loan-Orca to pay for it is now what's killing him!

Fleeing or Surrendering

For player characters, whether to surrender or try to flee, is generally their player's choice. Major NPCs should have enough of their personality and motivations defined that the GM can make that call on their behalf.

For player characters, and major NPCs, a forced-retreat may also occur in response to something that explicitly attacks their Current Wilful score, such as certain magics or elixirs, or the GM (or player) deciding that a phobic weakness of the character is relevant to the situation.

In this case, the cause of the fear will have been assigned a success chance which is played against the character's Current-Wilful score, plus appropriate skill/weakness modifiers, in either an Opposed Task or a Combat roll.

For minor NPCs, this is generally more effort than one would want to apply, so these entities might decide to flee if any of their current-characteristics drops too far below the Base value, usually down into the range of single-digits. A certain amount of judgement from the GM should be exercised here for NPCs, considering their motivation to fight in the first place, and what they may believe to be the consequences of fleeing or surrendering would be for them.

Ask yourself: are they sufficiently frightened, hungry, paid, socially pressured, deluded, or just plain stupid or crazy enough to really risk dying in this battle?

This should not apply to entities that cannot, for some reason, do so. For example, a cornered enemy can't flee; an enemy fighting for something they value more than their own life probably won't flee or surrender; an enemy with no self-will (such as the Re-lived from the Octas/fallen genre module) have no autonomy over their instincts and cannot flee or surrender.

Non-sapient ("dumb") animals are generally a lot better at quickly judging flight vs fight than sapient beings, who tend to over-think such things: the latter's decisions tend to be heavily weighed down by a whole bunch of social, moral and self-delusional considerations that animals don't have to deal with.

To flee, a character must actually leave the combat zone. This involves using one or more combat rounds to move at the characters maximum speed (see character movement), away from danger. If tracking combat on a map, this means moving either to effective cover marked on the map, or off the edge of the map. If the combat is not being conducted with reference to a map, it can be considered to require moving outside of the attacker's weapons range, however many combat rounds that requires at the character's maximum movement speed. Don't forget that the attacker can likewise use a combat round to chase at their own maximum movement speed, to try to keep their opponent within combat range!


Different creatures/species have different unencumbered movement rates for land, water and air.

For simplicity we count 'water' as both on the surface and below.

For humans, it is:

Medium Base Speed
Land 8
Water 2
Air 0

Humans can fly unassisted. But only strait-down, which counts as 0-movement on a 2D map!

For unencumbered maximum movement speed, add the base speed to the Phy Bonus.

For encumbered characters on land or in water, apply the additional table:

Carried Weight (in blocks) Effect (Land and Water)
Up to half of Physical x 8 Normal movement speed
Half to equal of Physical x 8 Half movement speed
Greater than Physical x 8 Cannot move!

You may be able to carry more under water (especially if what your are carrying is somewhat buoyant) but you can't carry it faster due to drag!

For characters that can fly in a direction other than strait-down, the thresholds are a lot tighter, with encumbrance beginning at equal to Physical, and over-encumbrance at two-times.

Carried Weight (in blocks) Effect (Air)
Up to Physical Normal flight speed
To Physical x 2 Half flight speed
Greater than Physical x 2 Cannot fly! (Take bus?)

The above table is for natural flight (crows and dragons, for example). Magical/technological flight may have different limits, as defined for the specific spell/device used.

In combat, this is the maximum number of lengths per combat round a character can move via that method of locomotion.

Some other factors:

Crawling is half-speed compared to walking, but carrying capacities do not change.

Moving carefully reduces movement speed by half, and also adds a +8 bonus to chances of detecting danger in the path of movement. This is in addition to any skills-bonuses in-play for this purpose.

Moving stealthily is likewise half-speed, providing a -8 detection penalty to any who might be on watch. This is in addition to any skills-bonuses in-play for this purpose.

Moving both carefully and stealthily applies both bonuses, but also slows one down to quarter-speed.

Combat Process

Actions and Reactions.

During each combat round, a character (player, or NPC) normally gets to perform one action. An action is initiated by the character. Examples of actions are:

Also during a combat round, a character may perform a (reasonably) arbitrary number of re-actions. Reactions are always an immediate response to an external event, and are generally the direct result of game mechanics. For example:

An Explicit Parry is an exception to the above. This is where the character specifies a parry defence as their action. This kind of parry is much stronger than a reactive parry: All of the character's current-score bonuses (high digits, if any, of all current-scores) are added. This number is then added to the character's defence for the duration of the Explicit Parry. This advantage comes at the cost of using up their action for the round, so they cannot attack or do any other things. An explicit parry starts at the character's turn and lasts until immediately before their next turn, and effects any attacks on the character during this time period.

Travelling Order

Normally, when travelling, a group should specify their travelling order, as if travelling in single file. Even if travelling as a loose cluster, this order can be considered as who is generally at the front and who is generally at the rear, and the actual numeric order considered a pure game mechanic.

This is one area were mini-figures, or even paper tokens, can be quite useful, as players can place their figures on the table in the order of travel and quickly re-arrange things as and when desired.

Players should specify their travelling order before setting out. Or before the start of the game they can specify a 'normal' group travelling order that will be assumed unless they explicitly state otherwise.

Or just go clockwise around the table if you want to be really lazy!

Travelling order can be changed any time the group is not engaged in an activity which would interfere with this change, such as combat, traversing a narrow passage, running away in blind terror...

Travelling order can determine who first encounters things, such as traps, aggressors, merchants, etc. (or encounters them subsequently, such as an attack from behind, traps set to trigger on the third person to trip them, being over-taken by a colourful parade of fire-eating marshmallow jugglers, etc.).

Combat Order

Before combat begins, the order of attack/defence is determined.

Firstly, all combatants are split into two groups: The un-surprised, and the surprised.

The un-surprised is anyone who is aware that the attack is coming, up to moments before it happens. This will be anyone initiating the attack, of course, but also anyone else who anticipates the attack, for example, by detecting a waiting ambush through a skill check.

The surprised is anyone who is not aware of the attack until it begins. This can be everyone involved, in the case of two opposing groups meeting with neither expecting the other.

The un-surprised go first. Within the un-surprised, there are two ways to determine order:

For a planned attack, the order of attack will have been pre-determined by the attackers. Roll DD once for each attacker and distribute the results lowest-to-highest in pre-decided attack order. For anyone else (eg, people who knew the attack was coming, but were not part of the planning), roll DD and insert them in the sequence according to their result. If two rolls are the same, the one who rolled the result first gets precedence.

For an unplanned attack, the order of attack will be either the attacking group's travelling order, with non-group un-surprised inserted as above. If the attackers have no defined travelling order, attack for all un-surprised is ordered off raw DD results.

The surprised have their attack/defence rounds after the un-surprised. Order is either the travelling order (or reverse travelling order if attacked from behind) or from pure random DD results if an order was not supplied or is not appropriate to the situation.

After the first round, continue each subsequent round of that combat event in the same order.

For example:

Defenders (travelling order): D1, D2, D3, D4; Attackers (planned attack order): A1, A2, A3.

Attackers are lying in ambush and attack from behind after the defenders have passed.

D3 notices the coming attack just before it happens, but not quickly enough to warn the rest of her group.

Attacker Order rolls: 51, 73, 12, Allocated in order as A1:12, A2:51, A3:73.

D3 gets an order roll of 53, and is slotted in between A2, and A3.

D1, D2, D4, are surprised from the rear, so in reverse marching order.

The order of attack for this combat session is: A1, A2, D3, A3, D4, D2, D1.

Once the order is determined, the dice-roll results are not used again, so can be discarded.

Possible alternate combat mechanic for consideration:

This means any (reasonably matched) combat will be around 50% hits irrespective of base skill levels.

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