METTLE Core
Version 1.88Core Mechanic
Roll a pool of d6s equal to the Attribute being used. Dice showing 1, 2, or 3 are summed as the Score; dice showing 4, 5, or 6 are counted as Edge. The Check succeeds if Score meets or exceeds the Difficulty (Routine 1 to Nigh Impossible 15), and Edge measures how well it went. On a failure with Edge, the player may call for a Twist — accept a complication proposed by the rest of the table, then reroll the Edge dice for a second chance. Initiative passes from the acting character to the target of their Action, who becomes the next to act. Mettle (Motive + Nature) acts as a combined morale and damage track, and characters may Surge by spending Mettle for bonus dice on critical Checks.
Best For
Groups who want fast pulp action-adventure in the vein of Indiana Jones, James Bond, or Tales of the Gold Monkey, with a hackable toolkit they can bend toward detective stories, wild-west gunfights, post-apocalyptic survival, or grounded science fiction.
Highlights
Score-and-Edge dice pool reads two outcomes from the same roll: whether the action succeeds (Score meets Difficulty) and how well it went (count of 4–6 dice). Player-invoked Twists let a failed roll be reframed as a messy success in exchange for a fictional complication chosen by the rest of the table. Six-attribute character sheet (Calling, Culture, Frame, Motive, Nature, Poise) replaces classes and skills with player-written Descriptors that justify which Attribute applies to a given task. Initiative passes from the acting character to the target of their Action, eliminating turn-tracking and tying combat order to who is acting on whom.
Considerations
Toolkit framing means the book provides scaffolding (factions, NPC seeds, sample castaway adventure) rather than a fleshed-out setting — groups expecting a defined world will need to build or borrow one. Mettle does triple duty as morale, hit points, and a spendable resource for bonus dice, which can take a session to internalize. Twist resolution depends on the rest of the table proposing complications, which slows play if the group is hesitant to add fiction.