METTLE Core vs Storypath Ultra

Compare METTLE Core and Storypath Ultra side by side. See differences in complexity, dice, genre, and more.

	METTLE Core	Storypath Ultra
Genre	Universal, Modern	Universal
Tags	Pulp Action, Toolkit, Hackable, Rules-Light, Classless, Fast-Paced, CC-Licensed Rules	Toolkit, Modular, Hackable, Investigation, Social Intrigue, Narrative, Classless
Core 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.	Roll a pool of d10s equal to Skill + Attribute. Each die showing 8+ is a hit; 10s count as two hits. Add Enhancement (bonus hits from gear, abilities, or circumstances). Spend hits to meet the difficulty, buy off Complications (side effects attached to the roll), or purchase Tricks (extra effects like knockdown or critical hits). Failed rolls generate Momentum, a shared pool players spend for bonus hits, to turn failures into successes, or to introduce story facts.
Dice	d6 dice pool	d10 dice pool
Complexity	Low	Medium
Availability	Free core rules	Paid
Runnability	5 of 5 book tools	4 of 5 book tools
License	CC BY 4.0	Proprietary (third-party license pending)
Third-Party Publishing	Not yet researched	Not yet researched
Publisher	Planarian Games	Onyx Path Publishing
Year	2021	2026
Languages	English	English
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.	Groups who want a genre-agnostic d10 dice pool engine with dedicated subsystems for action, investigation, and social intrigue: especially those building their own setting or adapting existing Storypath games.
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.	Three distinct play modes (action-adventure, investigation, and influence) each with dedicated mechanics. Complications and Tricks give every successful roll narrative texture beyond pass/fail. Momentum turns failed rolls into a shared resource that keeps the story moving. Modular building-block systems (powers, heists, vehicles, crafting, large-scale combat) plug into any game.
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.	No included setting beyond three short examples: groups must build or adapt their own world. No free quickstart or SRD available. Multiple interacting subsystems (Enhancement, Advantage, bonds, Complications) take several sessions to internalize.