Itty-d20

itty-d20
one page rpg
No. of Players	4 + GM
Session Time	2 - 4 hours
First Publication	2020

itty-d20 is a role playing game framework with simple rules. Inspiration comes from microlite RPGs and games played with d20s, but unlike some of those games, this one has no rules for magic. Improvements to the game are welcome. It's released under the Creative Commons Zero (Public Domain) license.

Character creation

• Characters have no set classes. Players select from a list of skills as they advance.

• Race is arbitrary. No advantages are granted.

• Basic attributes like fitness and agility are gained through training. Charisma and intelligence are based on the player's role playing performance and investigative skills. There is no need for extra attributes like wisdom or constitution.

• Max HP is always 20 for all player characters.

• Armor Class (AC) is 10 + plus modifiers from armor and training.

• Passive perception is 10 + the perception modifier.

Rolling Dice

1d20 means roll one 20 sided die.

• Initiative: d20 + agility modifier
• Attack rolls (AR): success: (d20 + AR modifiers) >= (opponent AC)
  • Rolling a 20 on the die always succeeds, and deals normal damage.
• Damage rolls: see weapon stats
• Ability check vs difficulty class (DC): (d20 + modifiers) >= (DC)
• Contests: (d20 + modifiers) > (d20 + modifiers). When both roll the same total, the contest is unresolved.

Combat

Players should inform the game master (GM) where they want to be relative to other players and non-player characters (NPCs).

Do one of the following on your round (lasts about 6 seconds):

• Move up to 5 meters (about 15 feet), and
  • Melee attack
  • Ranged attack
  • Non-combat action
• Move up to 10 meters
• Run up to 20 meters, opening up to attacks of opportunity

Coma / Death

If a player reaches 0 HP, they enter a coma. If they lose 3 more HP beyond that, they die.

Rest

A long rest is 8 hours, uninterrupted. A short rest is 1 hour. The max rest is 1 long rest, and 2 short rests per day.

After a long rest, all regain 1d8 HP. After a short rest, 1d4 of health is restored. Before rolling, use of a medicinal kit during a rest period increases HP by an additional 3 points.

Advancement

Players start at level zero. One experience point (XP) is gained per approximate hour played.

• XP -> levels
  • Level 1: 1 XP
  • Level 2: 3 XP
  • Level 3: 6 XP
  • Level 4: 10 XP
  • Level 5: 15 XP
  • Level n: (level n-1 XP) + n

XP is cumulative, so it doesn't reset after each level. There is no max level.

Training

Players start with two skill points, and gain one per level.

Skills cost 1 skill point per level, and have no max level, unless otherwise noted.

• Fighting
  • Skill with melee weapons (+1 AR)
  • Skill with ranged weapons (+1 AR)
  • Second attack (-5 AR modifier on second attack) (May only be used with weapon classes for which there is a skill level of at least 5) (cost: 2 skill points) (max: 1 level)
  • Self defense (+1 AC)
• Special ability checks
  • Agility
  • Fitness
  • Scholarly knowledge
  • Medicine
  • Nature, survival
  • Perception
  • Sleight of hand
  • Stealth

Equipment

100 copper = 10 silver = 1 gold

The GM determines characters' starting wealth.

Max carrying weight: 50 + fitness * 10 Kg. Characters are burdened when carrying over 25 + fitness * 5 Kg.

• Weapons
  • Melee
    • Unarmed: 1
    • Dagger: 1d3 (2 gold)
    • One handed axe: 1d4 (4 gold)
    • One handed sword: 1d6 (10 gold)
  • Ranged
    • Bow and arrow: 1d3 (10 gold) (range 20 meters; -5 AR for 11-20 meters)
    • Cross bow: 1d4 (30 gold) (range 20 meters; -5 AR for 11-20 meters)
• Armor
  • Light armor: AC +1 (3 gold)
  • Medium armor: AC +2 (30 gold)
  • Heavy armor: AC +3 (60 gold) (-3 on stealth checks)
  • Shield: AC +1 (2 gold)
• Survival
  • Food ration (1 silver)
  • A day's worth of potable water (1 silver)
  • Traveling clothing (1 silver)
  • Tent (5 gold)
• Medicine
  • Medicinal kit (5 silver)
• Gear
  • Rope (1 silver / meter)
  • Grappling hook (1 gold)
  • Tinder box (5 silver)