What is a Difficulty Class (DC) in SWURPG?

The Difficulty Class (DC) in SWURPG is the target number you must meet or beat with your d20 roll and modifiers to succeed at an action. Very Easy tasks might be DC 5, average tasks DC 15, and extremely difficult tasks DC 25 or higher.

How do Advantage and Disadvantage work in SWURPG?

In SWURPG, Advantage and Disadvantage work like D&D 5E. With Advantage, you roll two d20s and use the higher result. With Disadvantage, you roll two d20s and use the lower result. Multiple sources of Advantage or Disadvantage do not stack, and if you have both on the same roll, they cancel out to a normal single d20 roll.

SWURPG Dice System – How Skill Checks Work

Q: How do I make a skill check in SWURPG?

To make a skill check in SWURPG, roll 1d20 and add your relevant Ability Modifier, your Proficiency Bonus if you are proficient in the skill, and any situational modifiers from gear, traits, or Force powers. If the total equals or exceeds the Difficulty Class (DC) set by the GM, you succeed.

Q: What happens on a natural 20 or natural 1?

On attack rolls, a natural 20 is always a hit and usually a critical success, while a natural 1 is always a miss. On skill checks and saving throws, a natural 20 or 1 does not automatically override the DC, but the GM may treat them as especially strong success or failure for narrative effect.

Dice System & Difficulty Class

In SWURPG, most challenges — from slicing into a locked databank to dodging a Sith’s Force strike — are resolved with one iconic tool: the twenty-sided die (d20).

Whenever success is uncertain, you roll a d20, add your bonuses, and compare the result to a target number called the Difficulty Class (DC). This simple core loop powers attacks, saving throws, skill checks, and many Force powers.

Core Dice Mechanic
Attacks, Saves & Skill Checks
Setting Difficulty Classes
Natural 20s & Natural 1s
Advantage & Disadvantage
Opposed & Group Checks
Example Rolls in Play
Dice System FAQ

The Core Dice Mechanic: d20 + Modifiers vs DC

Any time the outcome of an action is uncertain and failure would matter, you usually follow this procedure:

Roll 1d20
Add the relevant Ability Modifier
Add your Proficiency Bonus (if proficient)
Add any situational modifiers (gear, traits, Force powers, Advantage/Disadvantage)
Compare the total to the DC

If your total equals or exceeds the DC, you succeed. If it falls short, you fail — or the GM may allow a partial success with complications to keep the story moving.

Example: Slicing an Imperial Databank
Ari Daxx attempts to slice a secure Imperial terminal using Use Computer.

GM sets DC 17 (Hard, high-security system).
Ari has Intelligence +3 and is proficient in Use Computer (+2 PB), for a +5 total bonus.

Ari’s player rolls 1d20 and gets a 12.

Total: 12 (roll) + 5 (modifiers) = 17 — exactly the DC.
Ari cracks the terminal, but the GM might add a twist: the slice succeeds, but triggers a silent alarm elsewhere in the facility.

Attacks, Saving Throws & Skill Checks

The same dice system governs three major types of rolls in SWURPG:

Attack Rolls

When you attempt to hit an enemy with a blaster, vibroblade, or Force-infused strike, you make an attack roll:

d20 + Ability Modifier + Proficiency Bonus + other bonuses

You compare the result to the target’s Armor Class (AC). If your total meets or beats their AC, the attack hits and you roll damage.

Saving Throws

Saving throws represent your ability to resist harmful effects — explosions, toxins, Force assaults, and more. A saving throw uses:

d20 + relevant Ability Modifier + Proficiency Bonus (if proficient) + bonuses

The GM or effect sets the DC. If the save succeeds, you usually take reduced or no effect; on a failure, you take full damage or suffer the condition.

Skill Checks

Skill checks cover everything else: sneaking through a hangar, piloting a starfighter in an asteroid field, negotiating with a Hutt, or patching up a wounded ally. Each skill is linked to an ability.

d20 + linked Ability Modifier + Proficiency Bonus (if proficient) + situational modifiers

If your total meets or beats the DC, you succeed. If not, you fail — or succeed with a cost, at GM discretion.

Setting the Difficulty (DC)

The GM sets the Difficulty Class (DC) based on how challenging the task is in the current situation. Use these numbers as a flexible guideline:

Typical DC Benchmarks

Very Easy (DC 5): Not much risk; almost anyone can do it.
Easy (DC 10): Basic training or a bit of luck required.
Moderate (DC 15): Standard challenge for trained heroes.
Hard (DC 20): Serious challenge even for specialists.
Very Hard (DC 25): Exceptional feats under pressure.
Nearly Impossible (DC 30+): Legendary actions, rare success.

Examples in Play:

DC 10: Jumping a short gap between catwalks under calm conditions.
DC 15: Convincing a suspicious dockmaster to ignore a cargo scan.
DC 20: Piloting a damaged freighter through an asteroid field at high speed.
DC 25: Slicing into a highly secure Imperial encryption node during a firefight.

Environmental conditions, gear, teamwork, and prior preparation can raise or lower the DC, or instead grant Advantage/Disadvantage or bonus/penalty to the roll.

Natural 20s & Natural 1s

Natural 20 (Critical Success on Attacks): Always a hit on attack rolls. Often triggers extra damage or a special effect depending on your weapon or class.
Natural 1 (Critical Failure on Attacks): Always a miss on attack rolls, no matter how high your bonus is.

For skill checks and saving throws, a natural 20 or 1 does not automatically override the DC, but many GMs treat them as especially strong success or failure:

A natural 20 might grant extra information, a bonus side-effect, or a faster-than-expected result.
A natural 1 might introduce complications, delays, or draw unwanted attention.

Use nat 20s and nat 1s to drive cinematic moments and memorable outcomes, not just math.

Advantage & Disadvantage

In SWURPG, the rules for Advantage and Disadvantage follow the streamlined mechanics of D&D 5E, adapted for the Star Wars setting.

🎲 Advantage and Disadvantage

Advantage: Roll two d20s and use the higher result.
Disadvantage: Roll two d20s and use the lower result.

When Do You Have Advantage?

You are hidden or unseen when making an attack.
You have clear tactical superiority (high ground, flanking, smart positioning).
A class feature, species trait, or Force power grants Advantage.
An ally uses the Help action or a similar supportive ability.

When Do You Have Disadvantage?

You are blinded, restrained, or prone while attacking.
Your target is heavily obscured by darkness, smoke, or full cover.
You are using a weapon or tool you are not proficient with.
Environment is working against you (zero gravity, strong wind, unstable footing).

Stacking Rules

Multiple sources of Advantage do not stack; you still roll only two d20s.
Multiple sources of Disadvantage also do not stack.
If you have both Advantage and Disadvantage on the same roll, they cancel out and you roll a normal single d20.
Two sources of Advantage and one of Disadvantage still cancel to a normal roll.

Example: Advantage in a Blaster Duel
A Rodian Marksman is hidden on a catwalk, aiming at a patrol of Stormtroopers below.

He has Advantage for attacking from hiding.
He also has a weapon mod that grants Advantage on the first shot each encounter.

Even though there are two sources of Advantage, he still rolls only 2d20 and takes the higher result. If the troopers somehow imposed Disadvantage (for example, by generating a smoke screen), the Advantage and Disadvantage would cancel out to a normal single d20 roll.

Opposed Checks & Group Checks

Not every roll is against a fixed DC. Sometimes, you roll against another creature’s effort.

Opposed Checks

In an opposed check, both sides roll and compare totals. Highest roll wins, ties usually favor the defender or maintain the current state.

Common Opposed Checks:

Stealth vs Perception: Sneaking past guards.
Deception vs Insight: Lying to an Imperial officer.
Athletics vs Athletics/Acrobatics: Grappling, shoving, or wrestling over an object.

Group Checks

For group tasks (sneaking as a whole squad, climbing together, etc.), the GM can call for a group check:

Each participating character rolls the relevant check.
If at least half the group succeeds, the group overall succeeds.
If more than half fail, the group fails — or succeeds with complications.

Group checks keep the party moving together without punishing everyone for a single low roll.

Example Rolls in Play

Example 1: Persuasion Check
A Diplomat is trying to convince a Hutt crime lord to delay payment on a hefty debt.

GM sets DC 18 (Hard negotiation with a powerful NPC).
The Diplomat has Charisma +4 and Proficiency in Persuasion (+2) = +6 total.

The player rolls 1d20 and gets a 13.

Total: 13 + 6 = 19 → success.
The Hutt agrees to a short delay, but adds a new condition: “Deliver a favor” on Nar Shaddaa in return.

Example 2: Dexterity Saving Throw
A thermal detonator lands in the middle of the squad. The explosion forces a Dexterity saving throw.

GM sets DC 15.
Orrin Daal has Dexterity +2 and is proficient in Dexterity saves (+2 PB) for +4 total.

Orrin rolls a 9 on the d20.

Total: 9 + 4 = 13 → failure.
Orrin takes full damage from the blast, while another ally who rolled 16 or higher takes half damage on a success.

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Dice System – Frequently Asked Questions

How do I make a skill check in SWURPG?

Roll 1d20, add the relevant Ability Modifier, add your Proficiency Bonus if you are proficient in the skill, then add any situational bonuses or penalties. If the total equals or beats the DC set by the GM, you succeed.

What is a Difficulty Class (DC)?

The DC is the target number you must meet or beat with your roll and modifiers. Easy tasks might be DC 10, moderate tasks DC 15, hard tasks DC 20, and very hard tasks DC 25 or higher.

Do I always roll for everything?

No. If an action is trivial or success is guaranteed, the GM can simply narrate success. Dice are reserved for moments of real uncertainty, risk, or drama.

How do Advantage and Disadvantage interact with other modifiers?

Advantage and Disadvantage only affect how many d20s you roll and which one you keep. You still add the same Ability Modifier, Proficiency Bonus, and other bonuses or penalties to the final result.

Can a natural 20 automatically succeed at anything?

On attack rolls, a natural 20 is always a hit. On skill checks and saving throws, natural 20s are not guaranteed auto-success for impossible tasks, but many GMs treat them as especially strong successes within the bounds of what’s realistically achievable in the scene.