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Thursday, 17 May 2018

D12 System Dev Diary 4

Saved by the works of someone better than I.

Should be the strap for this post. The longer version is that I kind of forgot that as a Cortex backer I have access to the SRD and Cam Banks has done a fantastic job of putting into words and dice most of the concepts I've been playing about with in systems development for this game. So I'm going to retool a bit and switch in that ruleset with a few amendments and variant rules applied to bring it in line with the overall game concept.

The best news about this switch is twofold. First I can reused the best bits of my prior attempt. e.g. Aptitudes and advantages as these were monumentally great from a world building perspective. Secondly, annoyingly tricky bits like damage mechanics are already built and tested which means I can concentrate on adding value elsewhere. For example, folding in the expansion content of bargains and the consequences (narrative and system) of where success comes from.

One other thing definitely making it in from Cortex is _ as this trait type has huge narrative potential.

Basically you write a statement that's true about your character. That gives you a pool die (D8) when it's relevant. if you the act against that truth you get 3D instead of 1 for that action and then it's stepped down to D6 for the remainder of play until you hit downtime and rewrite it.

Here are a couple of examples.

You have the statement "I always have Jeff the Merc's back". Which means you get a die whenever you're backing Jeff up.
But for the last couple of sessions Jeff has been a bit of a tool so the next time you, in a righteous rage, throw him to the wolves. you get 3D this time around and in downtime you rewrite you statement as "Watching out for Jeff"

You are a big fat panda and write that "I've had the noodle dream" so you get a bonus die when doing noodle shop stuff.
At a later point you then confess that you lied and that you love kung fu. 3D for riding a firework chair into the stadium etc. and in downtime you change "noodle dream" to "kung fu dream"

anyways. the rest of this dev diary series will focus on the Cortex SRD implementation and maybe I'll even come up with a better name for it...

Monday, 14 May 2018

D12 System Dev Diary 3

Aptitude and Advantage seem to be working fine so far. Generated a lot of good chat and added plenty sidebar content to local world building.

I'm still not sure that the core mechanic is going to work though. Split pools may be too small in real combat and may just act as a break on the action so I'm reviewing this and coming up with some alternatives.

Playbooks really don't work for the open box setup. There are just too many possibilities to try and account for so I think I'll move to a life path style for future characters.

I'm interested to see if simply a collection of advantages would better reflect what I'm aiming for given the quality of play so far off limited information.

Design of the magic system is still giving me the cold sweats as I know the feel I want to give but mechanically its the hardest part to balance.

Also still to bottom out is the damage/survival mechanism. I had an old idea for weapon cards that I might dig up and try out.

I also have an embryonic idea about chaining actions together but this probably only works for combat and I wasn't keen on separate resolution mechanics but again I may try that out.

I may simply have to become accepting of higher levels of abstraction to get the game to work in an OOG environment that is pressed for time.

Tuesday, 8 May 2018

D12 System Dev Diary 2


Aptitudes are broad areas that you have a natural talent or affinity for. An aptitude grants 1D for any appropriate action test.

Aptitudes are recorded on your playbook in the form

Natural born _

Some examples are:

All characters begin the game with a single aptitude.


Your ability score represents the time you have invested in training and developing a specific skill or area of knowledge.

Monday, 7 May 2018

D12 Setting Dev Diary 1

The thin breeze failed cut the stench inside the wagon, merely rearranging it into an equally unpleasant miasma. Comfort not being high on the agenda of chainers, the the wagon train bumped and rolled with the gait of the huge folak harnessed to it. The beast itself looked to be in poor condition, great curtains of dry skin sloughing from its sides, huge tongue lolling to one side.

The guards escorting the caravan looked almost as discomforted as their charges. Mercenaries for the most part with a few company men alongside. Faces wrapped against the ever present dust most walked alongside the train. A few outriders ranged off to the fore and aft and the ubiquitous horta caravan dogs loped around vainly hoping for scraps.

In the distance, the faint rumble of the great falls and their penultimate destination, Anvall, City of Chains.

At the head of the train Ioan was one the first to catch sight of the great dome of the Chainers Hall. Soon they could offload their stinking cargo to the kind ministrations of the placement officers. After that he would have enough put by to sign on with a Velaki crew and sail for Planos.

He would be well rid of the Nassi tribesmen with their strange eyes and that beast Rolk the Ugir. Best of all the sea air would rid his nostrils of the scent of hopelessness that hung about the train like fog.

D12 System Dev Diary 1

What's all this about?

This work is directly inspired by both Evil Hat's Fate Core and John Harper's excellent Blades in the Dark. Indirectly by a 30+ year history of analogue and computer gaming. I was looking for something to use for an open world FRPG and although I love both Blades and Fate, neither was quite the right fit for the feel of the game I want to run. So what started as a Fate/Blades hack has become something rather more. This version  unashamedly uses a bucketload of d12's because they give the results curve a nice shape and they roll nicely.

I wanted to retain player agency so similarly to Blades only the players roll dice in most circumstances. There's going to be all manner of conflict in this game and so I wanted to generate a feel of dynamism which I'm hoping to do with advantages.

Taking action

There is no need to make an action test if:
  • an action has no reasonable chance of failure
  • failure would not produce an interesting  complication 
  • failure would not move the story forward
  • failure does not add dramatic tension
In any of these cases the action should be narrated as having succeeded without rolling dice. Otherwise, an action test is required
  • Build a dice pool
  • Split the pool into action and reaction dice
  • If you act first the roll action dice and check the result
  • If you need to make a reaction roll those dice and check the result

Building your pool

  • Start with a number of dice equal to your ability.
  • If your aptitude applies add 1D
  • Use an advantage to add 1D
  • If the action is above your ability then subtract 1D
  • For each complication subtract 1D
  • When an opponent has the advantage subtract 1D
  • Physical actions add 1D and have a minimum pool of 1D
If the action is directly opposed then split your pool into action and reaction dice.

You will usually have a choice of whether to act or react first but sometimes circumstances will dictate who acts first.

Rolling the dice

Roll all your (re) action dice. Highest number counts.

If your highest result is:
  • 1-3 you flub your action in the worst possible way and probably give your opponent the advantage.
  • 4-6 things are not going your way. you fail to achieve the outcome you wanted.
  • 7-9 glass half full. you managed to do it but at a cost.
  • 10-11 done deal. your action plays out exactly the way to wanted.
  • 12 stylish. success with flair, increased effect, start a chain or +1 advantage.
If your top result is 10-12 then for every extra 10-12 result you get you gain +1 advantage.


Advantages come in two flavours, immediate and perpetual.

Immediate advantages are usually the result of action test rolls and can be spent on the task at hand only. They can not be carried over to new tasks, although they may be carried over to different types of actions that are part of the same task where appropriate.

Immediate advantage is lost when:
  • The task at hand has finished (complete or otherwise)
  • It is spent on actions to accomplish the task at hand.
  • When it is squandered (a 4-6 max result)

  • When it is taken from you (a 1-3 max result)
Perpetual advantages are usually gained from equipment, training, secret knowledge, magic or other means. They can be used on multiple tasks and often on multiple actions in a task.

Using your advantage

Advantages can only be applied to actions following the action that generated them. 

They can be used before the roll for +1D each
They can be used after the roll to buy up a result on 1D, e.g. turning a 1-3 result into a 4-6 result etc.
If you buy up to a 12 result then that result does not generate advantage but may be used for flair, increased effect or to start a chain.

That's it for D12 Dev Diary 1, next up some worked examples and a touch of world building.