Thread by @pyrofoux

I improvised a dice roll mechanic last night for an impromptu rp game, and it turned way more interesting than expected:

Roll a D20. Look at the current time on your phone.
Your score is the number of digits on your phone that are also on the D20. I call it a “Clockroll”. 🧵

If you rolled a 17, and the time is 13:17 your clockroll score is 3.

0 = Failure
1 = Success
2 = Great success
3 = Legendary success
4 = Impossibly great success

We both discovered the mechanic while playing. My player loved the act of checking her phone after a roll, calculating herself if she did well or not.

There's this little suspense after the roll where she goes "Okay I rolled this. Is it actually good right now, though?"

Remember that it was an improvised on the spot game, with very little preparation. There's 2 main challenges with those:

1. Character Personalisation. You can't spend too long translating your PC into stats. There's a good chance your player will create the character as they go.

Meaning, there's no quick and easy way to know if they're good at something and translate it into the rolls. On a pure mechanical level, they don't have an identity.

2. Drive. No preparation means no time to figure out a motivation for the PC to go along with the story.

That's fine. They'll just wander around and you'll see where the story goes. It also means it's way harder to raise tension, to create a stake that needs to be resolved, a situation where they're hooked into and want to see to the end.

What's cool is that this simple clockroll mechanic helps on both fronts. To see why, let's plot your average clockroll score along time.

I wrote a little Python script to visualize it. Time of the day on the X axis, average score on the Y.

As often with time series, you have a shorter cyclical pattern at a lower scale that makes it harder to see what's happening.

Let's split it in 2: one graph for the hour digits (left) and one for the minute digits (right)

To know your odds of success, you just add the value for the hours with the one for minutes.

There's a dynamic at the scale of one hour: a short lucky phase, and bad luck otherwise, with some spikes every 10 minutes.

At the scale of the whole day: You have a huge spike of luck around noon, that sustains for a while. But as the sun is setting, you're dangerously close to a night of a bad odds where everything will get harder.

Now back to our game. We started playing around 6pm. It turned out to be a *perfect* time for story progression.

That leaves one hour for setting the stage and some characters. Then we throw some challenges, and this is where this mechanic shines.

My PC wakes up in a flying ship. She's helping a junior sailor find a missing crew member that is also the mechanic. If they don't find him in time, the ship crashes.

So my PC wanders in the ship, jokes a bit with the sailor. She loves the setting, and is playful with it.

That's good! Now that she's attached, let's turn up the heat. A detective that shoots before asking questions appears, and they get wrangled up in a fight.

My PC is trying to handle it, and hides away to think about how to fight this guy. Then she realizes something.

The clock shows 19:45. Remember that hour cycle graph? By now, the PC has an instinct of how it works: in 15min, it will be 20:00 and she will have a way harder time fixing this whole situation.

She has 15min to find a solution or things will get way worse. The clock is ticking.

Implicit choice: she could take longer and find a sure-fire solution instead but -- it's not who she is.

She decides to immediately takes more risks, before the risks get even riskier. She gets back into the fight with a sense of long scale urgency.

Do you see how this helped with both Personalisation (1) and Drive (2)?

By giving her a choice between acting now or risking things to get worse, it helps getting her hooked and thinking about long term at the scale of the scenario.

It's also allowing her to express how she wants to spend her resources between Time and Skill. She impacts the world in her own, specific way not only in narration but in mechanics too.

And all that, without even asking her who she is. Just give her a D20 and a clock.

The mechanic could probably get tweaked one way or another --but for an improvised on the spot rpg it was simple, and excellent. Letting your PC discover it is a huge part of the fun.

Want to see what happens with another dice? The code I wrote➡️pastebin.com/RkQCG0T8

FIN

BONUS: This mechanic was great for the short scenario: "A boat is about to crash and you have to stop it" & it can also fit other themes. The day/night cycle could be great for vampire stuff. Or you're a chronomancer and you can tweak the dice to get the most of the current time

Nothing goes through publication without damage, lol. Line 21, replace "_die_score" with "_dice_score"

ERRATUM: There was a tiny error in my code. The actual graphs have a roughly similar shape but a different magnitude.

Also here's a version of the code that can also handle complex rolls like 2D6+4
🔗pastebin.com/7zuudpLV