Powered by the Apocalypse (2d6 + stat)

At the table

In Powered by the Apocalypse games (Apocalypse World, Dungeon World, Monster of the Week, and many others), you roll 2d6 + stat and read the total:

There is no separate “natural 20” on the dice; the whole outcome is the total (2d6 + stat). That is exactly what lesson 7’s bucket is for.

Try it

In the playground, open this lesson in the playground and click Run (or press Shift+Enter).

The script

↗Scale = scale().step("MISS", ..6).step("PARTIAL", 7..9).step("FULL_SUCCESS", 10..)
STAT = 2

roll = 2d6 + STAT
out = roll.bucket(Scale)
output("move", out)
output("p_full_success", out.p_at_least("FULL_SUCCESS"))
output("p_partial_or_better", out.p_at_least("PARTIAL"))

• 2d6 + STAT is the usual PbtA notation (lesson 3); same odds as shift(2d6, STAT) if you prefer the function form.
• Bands on Scale give one inclusive interval per label; roll.bucket(Scale) uses them (same odds as bucket(roll, scale, [6, 9]) with a label-only scale).
• p_at_least("PARTIAL") is the chance you do not miss (partial or full).

Reading the result

You get a three-row probability breakdown for the move, plus scalar probabilities for full success and for “7+” style outcomes.

With STAT = 0, the bands match the core rulebook: 15/36 miss, 15/36 partial, 6/36 full success on the 2d6 alone.

Try this

• Set STAT to a typical score for your playbook (+0, +2, +3).
• Compare p_full_success across stats in a small loop (lesson 10 style) if you want a chart.

What’s next

See the user guide index. Lesson 12 buckets the natural d20 with scale().step(...); PbtA totals use the same builder with bands on the total.

move · Outcomes

p_full_success · Prob

p_partial_or_better · Prob