TRPG Glossary

An explanation of commonly used TRPG terms in alphabetical order. A terminology dictionary that even beginners can understand immediately.

TRPG Glossary

Terms frequently used in TRPG organized alphabetically. If you're a beginner and come across an unfamiliar term, check this page.

A

AC (Armor Class)

Meaning: Defense rating. Difficulty of avoiding attacks.

Calculation:

AC = 10 + Dexterity modifier + Armor bonus + Other

Example:
Dexterity 14 (+2) + Leather Armor (+1)
→ AC 13

Important: Attackers need to roll AC or higher.

Advantage

Meaning: During dice roll, roll two d20s and take the higher result.

Example:

Attacking with ally support
→ Roll with advantage
→ Results: 7 and 16 → Take 16!

Related: Disadvantage

B

Bonus Action

Meaning: An additional action separate from regular action.

Examples:

- Second attack with dual wielding
- Rogue's hide
- Bard's inspiration

Limitation: Once per turn only.

Buff

Meaning: Strengthening effect on allies. Increases attack power, defense, speed, etc.

Example:

《Bless》spell
→ All allies get +1d4 to attack rolls
→ Lasts 10 minutes

C

Class

Meaning: Character's profession. Fighter, wizard, rogue, etc.

Main Classes:

Fighter types: Fighter, Paladin, Barbarian
Magic types: Wizard, Cleric, Warlock
Skill types: Rogue, Ranger, Bard

Importance: Skills and equipment vary greatly by class.

Critical Hit

Meaning: Great success when rolling 20 on d20. Damage is doubled.

Effect:

Normal attack: 1d8 + 3 → Average 7 damage
Critical: 2d8 + 3 → Average 12 damage!

Also:
- Destroys enemy armor
- Dramatic description
- Changes battle situation dramatically

Critical Miss

Meaning: Great failure when rolling 1 on d20. Automatic failure.

Example:

Sword attack → Critical miss
→ Sword slips and cuts your own foot!
→ Takes 1d4 damage

D

Damage

Meaning: Damage received from attacks or traps. HP decreases.

Types:

Physical Damage:
- Slashing (sword, axe)
- Piercing (spear, arrow)
- Bludgeoning (club, fist)

Elemental Damage:
- Fire
- Cold
- Lightning
- Acid
- Poison
- Psychic

DC (Difficulty Class)

Meaning: Check's target number. Success if you roll this number or higher.

Difficulty Guidelines:

DC 5  - Very easy (almost automatic success)
DC 10 - Easy (average person succeeds)
DC 15 - Medium (requires some skill)
DC 20 - Hard (expert level)
DC 25 - Very hard (even masters may fail)
DC 30 - Nearly impossible (legendary)

Dice

Meaning: Polyhedral dice used for checks. d20 is most important.

Types:

d4  - 4-sided die (tetrahedron)
d6  - 6-sided die (cube)
d8  - 8-sided die (octahedron)
d10 - 10-sided die (decahedron)
d12 - 12-sided die (dodecahedron)
d20 - 20-sided die (icosahedron) ★Most important

Disadvantage

Meaning: During dice roll, roll two d20s and take the lower result.

Example:

Attacking in darkness
→ Roll with disadvantage
→ Results: 18 and 5 → Take 5...

E

Encounter

Meaning: Players encountering enemies or obstacles. Scene where combat begins.

Types:

Random encounter (chance meeting)
Fixed encounter (inevitable battle)
Event encounter (important story-related meeting)

Experience Points (XP)

Meaning: Growth points gained from adventures. Level up when enough accumulates.

How to Gain:

Defeat enemies
Complete quests
Solve mysteries
Make important discoveries

F

Fumble

Meaning: Another name for critical miss. Great failure when rolling 1 on d20.

G

GM (Game Master)

Meaning: Game facilitator. Story narrator and also plays enemy roles.

Roles:

1. Scenario progression
2. Acting as NPCs
3. Setting check difficulties
4. Rule arbitration
5. World description

In this app: Automatically handled by AI GM!

Gold (GP)

Meaning: In-game currency. Used to purchase equipment and items.

Price Guidelines:

1 GP = One night at cheap inn
10 GP = Ordinary sword
100 GP = Luxury armor
1000 GP = Magic item

H

Healing

Meaning: Restoring HP (Hit Points) after taking damage.

Methods:

Healing magic (cleric spells)
Potions (healing potions)
Rest (short rest/long rest)
Natural recovery (when leveling up)

Hit Points (HP)

Meaning: Character's stamina/life force. Unconscious at 0.

Important:

HP > 0  : Healthy
HP = 0  : Unconscious (death saves begin)
HP < 0  : Risk of instant death

Recovery Methods: Healing spells, potions, rest

I

Initiative

Meaning: Action order determined at combat start. Decided by Dexterity check.

Example:

Combat begins!
Player: Initiative 18
Enemy A: Initiative 12
Enemy B: Initiative 8

Action order: Player → Enemy A → Enemy B

Inventory

Meaning: List of items character possesses. Contents of bags or pouches.

Important Points:

Weight carrying limit exists
Don't forget important items
Keep frequently used items easily accessible

L

Level

Meaning: Character's growth stage. Higher number means stronger.

General Classification:

Lv.1-4  : Beginner
Lv.5-10 : Intermediate
Lv.11-16: Veteran
Lv.17-20: Heroic

Level Up

Meaning: Growth when experience points reach a certain amount.

What You Gain:

- HP increase
- New skills and spells
- Ability score improvements
- Class feature enhancements

M

Magic

Meaning: General term for spells using supernatural power.

Users:

Wizard (arcane magic)
Cleric (divine magic)
Warlock (pact magic)
Bard (inspiration magic)

Magic Item

Meaning: Item with special powers. Powerful but rare.

Rarity:

Common      - Common magic items
Uncommon    - Somewhat rare
Rare        - Rare
Very Rare   - Very rare
Legendary   - Legendary grade

Modifier

Meaning: Bonus value calculated from ability scores. Added to dice rolls during checks.

Calculation:

Modifier = (Ability Score - 10) ÷ 2 (round down)

Example:
Strength 16 → Modifier +3
Dexterity 12 → Modifier +1
Intelligence 8  → Modifier -1

Monster

Meaning: Creatures appearing as enemies.

Types:

【Animals】
- Wolves, Bears, Giant Spiders

【Undead】
- Zombies, Skeletons, Ghosts

【Monsters】
- Goblins, Orcs, Trolls

【Dragons】
- Red Dragon, Blue Dragon

【Fiends】
- Demons, Devils, Elementals

N

NPC (Non-Player Character)

Meaning: Characters not controlled by players. Played by GM.

Types:

【Important NPCs】
- Quest givers
- Key story figures
- Allied companions

【Common NPCs】
- Villagers
- Shopkeepers
- Passersby

O

Opportunity Attack

Meaning: Additional attack possible when enemy tries to flee from nearby.

Conditions:

1. Enemy moves away from adjacent square
2. Your reaction is available
3. Enemy is visible

→ One attack possible!

P

PC (Player Character)

Meaning: Character controlled by player. Adventure protagonist.

Antonym: NPC (Non-Player Character)

R

Role-Play (RP)

Meaning: Acting as the character.

Example:

【With Roleplay】
"I draw my sword and say in a trembling voice,
'I'm ready... come at me!'"

【Without Roleplay】
"I draw my sword and take combat stance"

Both are correct: Play style is free!

S

Saving Throw

Meaning: Check to avoid danger. Used to escape enemy magic or traps.

Types:

【Physical】
- Strength save: Resist being pushed
- Dexterity save: Avoid traps
- Constitution save: Withstand poison

【Mental】
- Intelligence save: See through illusions
- Wisdom save: Resist fear
- Charisma save: Break charm

Scenario

Meaning: Blueprint for TRPG adventure. Story, enemies, treasure chests, etc. are defined.

Structure:

Introduction → Development → Climax → Conclusion

Session

Meaning: One gameplay. Time from start to finish.

Duration:

Short session: 1-2 hours
Standard session: 3-4 hours
Long session: 5+ hours

Spell

Meaning: Magic usable by wizards and clerics.

Types:

【Attack Spells】
- Fireball (flame ball)
- Lightning Bolt (lightning)

【Healing Spells】
- Cure Wounds (heal wounds)
- Healing Word (healing words)

【Support Spells】
- Buff (ally enhancement)
- Debuff (enemy weakening)

Limitation: Limited uses per day (spell slots).

T

Turn

Meaning: One person's action order during combat. Can act when your turn comes.

What you can do in 1 turn:

- Movement (up to maximum speed)
- Action (attack, spell, dash, etc.)
- Bonus Action (specific skills)
- Reaction (opportunity attack, etc.)
- Free Action (short conversation, etc.)

W

Wild Shape

Meaning: Druid-exclusive ability. Can transform into animals.

Example:

Transform into bear
→ HP increase, claw attacks possible
→ Infiltrate places humans can't enter

X

XP (Experience Points)

Meaning: Abbreviation for experience points. → See Experience Points

Numbers

1d20

Meaning: "Roll one 20-sided die".

Notation Rules:

2d6  = Two 6-sided dice
3d4+2 = Three 4-sided dice + modifier 2
1d20+5 = One 20-sided die + modifier 5

For More Details

For details on each term, also refer to the following guide pages:

What is TRPG - TRPG basics
Dice System - Check mechanics
Character Creation Guide - Class and ability score details
Scenarios Guide - How to choose scenarios

📖 If you encounter an unfamiliar term, come back to this page anytime!