Chapter 5 — The Core Mechanic

Everything in Part II builds on this chapter. When the outcome of an action is uncertain and the stakes matter, the GM calls for a test. This is how tests work.

Index§

• The roll
• The probability
• What the GM calls for
• Difficulty
• Degrees of outcome
• Opposed tests
• When not to roll

The roll§

Roll 2D6, add your relevant skill bonus, and meet or beat 8.

2D6 + skill bonus ≥ 8 = success

That's the whole system. Everything else is detail.

The probability§

The 2D6 distribution clusters around 7 — the most common result on two dice. This means a flat roll with no skill bonus is slightly more likely to fail than succeed. Skill is not a nice-to-have; it is what tips the odds in your favor.

Chance of success at the default target of 8+, by skill rank and by whether the relevant characteristic grants Advantage, nothing, or Disadvantage:

The Neutral column is the baseline; Advantage (3D6 keep highest two) and Disadvantage (3D6 keep lowest two) reshape the curve rather than sliding it, which is why their effect is largest in the middle ranks. See Chapter 6.

What the GM calls for§

The GM specifies:

• Which skill applies — usually obvious from what the character is doing
• Which characteristic — each skill has a default, but the GM can call a different one when the situation warrants (e.g., Survival rolled under Intellect to plan a route rather than Endurance to endure the terrain)

The player then rolls, applying any Advantage or Disadvantage from the relevant characteristic.

Difficulty§

The target number is always 8. Wanderstar never raises it for a hard task or lowers it for an easy one — difficulty lives everywhere except the target. A fixed 8 keeps the odds legible (the table above never shifts) and keeps Advantage and Disadvantage the single currency of "how hard is this," rather than splitting difficulty between a moving number and the dice. To make something harder or easier, reach for one of these, never a bigger or smaller number:

Whether to roll at all. The bluntest dial is the test itself. A task with no meaningful chance of failure isn't rolled — it simply succeeds; one with no meaningful chance of success isn't rolled either — it simply fails (see When not to roll, below). Most difficulty calls are really this one: is this genuinely uncertain for this character?

Advantage and Disadvantage. Among the things worth rolling, conditions set the odds. Good light, the right tool, time to work, a sound plan, a helping hand → Advantage. Bad footing, improvised tools, haste, exhaustion, a hostile environment, working blind → Disadvantage. This is the main difficulty knob, and it is already priced: a situational Advantage the GM grants costs the player 1 Momentum, while a Disadvantage the GM imposes is free and feeds the player Momentum (see Chapters 6 and 7). Sources don't stack — three reasons a task is hard still impose a single Disadvantage — but one reason either way is usually enough.

Skill and training. Which skill the GM calls, and whether the character is trained in it, already encodes a great deal. The Untrained −3 is the system saying this is hard because you don't actually know how. Some tasks the GM may simply gate: not attemptable below Trained, or impossible without the right gear, knowledge, or access.

Raise the stakes, not the number. The honest way to make a roll matter more is to make failure cost more — not to move the 8. A barely-made roll can carry a complication; a near miss can offer success at a price (see Degrees of outcome, below). A hard, important task is one where the GM has made the consequences bite.

Make big things take more than one roll. When a task is hard because it is large — slicing a fortress network, performing field surgery, talking a hostile council around — don't reach for an unreachable number. Require several successes before a set number of failures (a progress clock), or run it as an extended contest (see Opposed tests). "Very hard" becomes "sustained competence under mounting pressure," which the 2D6 curve models far better than one roll against a high target.

In short: the number is always 8. To make something harder, ask whether it should be rolled at all, lean on Disadvantage, gate it behind training or gear, raise what failure costs, or demand more than one success — never a bigger number.

Degrees of outcome§

Wanderstar does not use tiered success levels by default — a test either succeeds or fails. However, the margin can inform narration:

• Making it by exactly 0: success, but barely — the GM may add a complication
• Missing by 1: a near miss — the GM may offer partial success at a cost
• Natural 2 (snake eyes): catastrophic failure, regardless of bonuses
• Natural 12 (boxcars): exceptional success, regardless of penalties — the GM may grant a bonus benefit beyond the stated goal

These are tools for the GM, not rules that demand mechanical outcomes.

Opposed tests§

Most tests pit a character against a fixed difficulty — the lock, the cliff, the failing reactor. An opposed test is for the other case: two characters pitting the same kind of effort directly against each other, where both have agency and either could come out ahead. A chase, a contest of wills, one character sneaking past another's watch, a lie weighed against a listener's scrutiny, two hagglers, a grappling match.

The procedure. Each side makes its own test — 2D6 + skill — applying its own Advantage or Disadvantage and paying its own Momentum as usual. The two sides may roll different skills: the sneak rolls Sneaking, the sentry rolls Recon; the liar rolls Deceive, the mark rolls Psychology. The higher total wins. The fixed target of 8 does not gate an opposed test — it is a head-to-head, and what matters is who clears the other, not who clears 8.

Ties. On an equal total, the defender wins — the side holding the status quo (staying hidden, holding ground, keeping the secret). The contest resolves in favor of nothing changing. Where neither side is the defender — two people lunging for the same dropped gun — a tie is an unresolved scramble: both may roll again, or the GM cuts straight to what happens next.

Margin tells the story. As with any test, how far the winner clears the loser colors the result. A runaway total leaves no doubt; a win by one or two is a near thing — the pursuer is still on your heels, the mark half-believes you, you pin them but they're squirming. The GM can hang complications on a narrow win exactly as on a barely-made test.

Extended contests. Some clashes aren't settled in a single roll — a long pursuit, a drawn-out negotiation, a battle of wits across a dinner. Run these as a short series of opposed tests, the GM framing each exchange and narrating the swing, until one side has clearly won (an agreed number of net wins, or simply when the fiction reaches its break point). Keep it short: the dice drive the scene, they don't replace it.

Opposed tests and combat. A fight resolves its clashes differently — an attack is a test against 8, and a target's resistance shows up as a reaction that imposes Disadvantage, not as a competing roll (see Chapter 11). Reserve opposed tests for contests outside the attack-and-defend exchange: the chase before the fight, the bluff at the checkpoint, the arm-wrestle in the bar.

When not to roll§

Not everything needs a test. If a character with Expert in a skill attempts something that isn't meaningfully uncertain, they simply succeed. Tests are for moments where failure is possible and interesting.