Generic Immediate System for Tabletop

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(Generic Immediate System for Tabletop)

CC BY-SA 2021 by Roberto Bisceglie

Version 1.5

This is a very freeform and streamlined ruleset, inspired by the Free Kriegsspiel Revolution and Old School Renaissance movements, based on the most famous old school sci-fi RPG, but intended to be used in any setting or genre. The system is designed to be very flexible and hackable. Hacks are indeed encouraged and welcomed.

Game System

Every action in the game is a task. Many of them can be adjudicate from the context and how the player describes the character performing them. Sometimes a check will be needed.


To determine the success of any task which outcome is not obvious nor granted, there are two types of check:

  1. Opposition Check: performed when two characters oppose one another. Both of them roll 2d6 and add modifiers, re-rolling ties. Who rolls higher wins.

  2. Target Number Check: performed, when the Referee determines a fixed difficulty, as follows:

    1. Roll 2d6.

    2. Add the roll modifiers granted by stats, skills or gear.

    3. Compare the modified roll to the target number: if the result is equal or greater, the action succeeds.

Target Number Difficulty
2 Trivial
4 Easy
6 Routine
8 Average
10 Hard
12 Very hard
14 Nearly Hopeless

Critical Rolls

A natural roll of 2 or 12 (without applying any modifier) is always a Critical Failure or Success.

Character generation

Character generation is very streamlined: you can start the game within minutes and the character sheets can be contained in an index card. The same procedure is used by the Referee to generate foes and NPCs:

  1. Roll 2d6 six times and assign to stats in order or as you wish. (Alternative) Distribute 46 points between stats as you wish.

  2. Choose an occupation for the character. The character is able to do anything related to their occupation as a Skilled Level skill. Tools of the trade are also taken for granted.

  3. Choose three skills and distribute among them 6 score points. The maximum score for a skill in character generation is 3.

  4. Give to the character a name and their age. Choose two items as starting gear.


  1. Might (MIG): physical prowess, power and strength.

  2. Agility (AGI): quickness, the ability of moving quickly and easily.

  3. Shape (SHA): physical resistance and ability to sustain stain and damage.

  4. Mind (MIN): the measure of intelligence, common sense and spiritual power.

  5. Knowledge (KNO): the measure of learning and experience.

  6. Personality (PER): emotional strength, personality and standing

Stats Scores

A Stat score determines both the Roll Modifier to apply to Checks and the Level to be used as a freeform qualitative indicator of the Stat rank.

The scale may go beyond 17. These scores are super-human domain. To determine a Roll Modifier take the score divided by 3, truncate decimals and then subtract 2.

Stat Score Roll Modifier Level
0 - 2 -2 Abysmal
3 - 5 -1 Poor
6 - 8 0 Mediocre
9 - 11 +1 Good
12 - 14 +2 Great
15 - 17 +3 Superb

Usually, a normal human being is limited to the maximum score of 15 (F). Other beings may exceed this limit.

Temporary scores

If circumstances impact negatively a character Stat, its score may temporary drop to a lower Level. For example, when when a character with a Good Personality loses a social contest, their Personality drops to Mediocre Level.


Any useful skill, in a situation that requires a check, grants as roll modifier equal to its score. The total score of all the character’s skill may not exceed the sum of Mind and Knowledge scores.

Skill Score Level
-1 Unskilled
0 Skilled
1 Competent
2 Professional
3 Veteran
4 Master

If characters attempt something out of their competence, they are Unskilled and suffer a Roll Modifier of -1.

The tone and the granularity of the skills list is determined by the Referee consistently with the chosen setting and genre. The following is a generic list which can be modified and expanded as seen fit:

  1. Athletic (agility, stamina, strength, sports)

  2. Artistic creativity, artist, musician, singer, actor)

  3. Intellectual (knowledge, wisdom, medicine)

  4. Magical (rituals, supernatural abilities)

  5. Martial (brawling, wrestling, combat, warfare)

  6. Primal (will, insight, fortitude, sixth sense)

  7. Skillful (“hands stuff”, tracking, burglary, sailing)

  8. Social (speaking, carousing, gossip, etiquette)


Any useful item, for a task that requires a Check, grants a +1 roll modifier.


Armor items grant a damage reduction ranging between 1 and 3, depending on the thickness.


Combat is a task checked by Opposition, split up in rounds. Every round a character has two actions chosen from: move, attack, defense, use of powers. It is possible to perform a double action (of the same type) forgoing the other.

The combat procedure takes place as follows:

  1. Each side determines initiative by rolling 2d6. Who rolls higher acts first. Agility and relevant skills modifier are applied to this roll.

  2. On their turn, characters take their actions.

  3. The round ends. Repeat steps 2-3 until the combat ends.

Once applied every relevant modifier (if a Critical is not rolled), the higher rolls wins.

Stat and Skills Modifiers are situational and depend also on the attack type. The Referee has to adjudicate which modifier is adequate to the situation.


A character has a total of Hit Points equal to Shape score multiplied by 2.

Every time an attacks blows on an opponent, the difference between the rolls is applied to the losing side as damage. Armor reduce the damage by its score.

If the parrying opponent throws higher than the attackers, this does not apply as damage.

A Critical is an automatic success/failure: the opponent HP is halved (rounded down).

When the total damage is equal to the Shape score, the character is wounded and maybe unable to use their Stat modifiers.

When the total damage is equal all HPs minus two, the character is severely wounded and unable to combat further. If a character blows on a severely wounded opponent, the latter may be dead or definitely out of combat. The winner chooses the opponent’s final fate.

When HPs drop to 0, the character falls unconscious and makes a Shape Check against 10+. On failure the character is dead.


A wounded character recovers half of their Hit Points if wounds are treated after the combat with bandages and medicament. A severely wounded character needs immediately medical treatment by an expert in a dedicate facility. If the treatment is not feasible, the character make a Shape Check against 10+ every hour. On failure, the character looses an amount of HP equal to the difference between the roll and 10. If HPs drop to 0, immediately perform the same check. On failure the character is dead.

After an amount of days equal to damage divided by 4 of rest a wounded character recovers their full HP. A severely wounded character need a hospitalization period in days equal to damage divided by 2 round up.


Every time a skill is remarkably challenged by the circumstances, the Referee may grant an Advancement roll to the player, rolling against 8+. On success, that particular skill gains an additional level.

Freeform Magic

Everyone with Magical skill may try to cast a spell. Spells are invoked by wording a simple frase composed by an action verb and an object.

To cast a spell a player has to make a Magical Check against the difficulty set by the Referee.

As a baseline, here is the Difficulty level by Magical:

Magical Difficulty
Unskilled Hopeless
Skilled Very Hard
Competent Hard
Professional Routine
Master Easy

Note that difficulty is situational and it is perfectly feasible in a desperate situation that even a Master may confront a Difficult task.


There are five main action verbs a character must state to set a spell:


There are six possible objects for a spell:


Magical can be a overpowering skill or not, depending on the chosen setting. To balance the potential overpower of Magical skilled characters, the Referee may define Accidents to make the use of magic more dangerous and risky.

Accidents may be bland or severe and should cause injury, mutations or even the loss of Magical skill itself.

Creatures and NPCs

Creatures are divided by size, having a different impact on their physical characteristics. Sentient beings are effectively NPCs, but they have no limitations on characteristics and abilities like humans. To build the other creatures, the reference table below may be useful.

Size Might Agility Shape
Tiny 1d3 1d6 1d3
Small 1d6 1d6 1d6
Medium 2d6 2d6 2d6
Large 3d6 2d6+2 3d6
Very Large 4d6 2d6 4d6
Massive 5d6 2d6-2 5d6
Colossal 6d6 2d6-4 6d6