Introduction

A Post-Apocalyptic Sci-Fantasy TTRPG System

What Is Ashfall?

Ashfall is a gritty, dark, and grounded tabletop roleplaying game set 50-100 years after a series of cascading catastrophes destroyed galactic civilization. This system emphasizes:

  • Tactical depth with adjustable lethality - DMs can dial encounters from cinematic to brutally realistic
  • Meaningful progression - Characters grow from desperate survivors to legendary figures over 20 levels (with optional mythic tier content beyond level 20)
  • Resource management - Equipment, augmentations, magic, and humanity are all finite resources
  • Hybrid flexibility - Mix tech and magic, combine archetypes, but always at a cost
  • Systematic balance - Clear rules for DMs to build encounters, distribute loot, and maintain challenge

Design Philosophy

Core Pillars

  1. Survival - Every resource matters in the wasteland
  2. Choice & Consequence - Power comes with trade-offs
  3. Emergence - Magic is new, alien, and unpredictable
  4. Rebuilding - Characters shape the future of scattered civilizations
  5. Grit - Healing is slow, death is real, victory is earned

Dice Mechanics

Primary Resolution Mechanic: d20 Roll

d20 + Attribute Modifier + Proficiency Bonus + Situational Modifiers

Target Numbers:

  • Skill Checks: Roll vs. Difficulty Class (DC 5-30)
  • Attacks: Roll vs. Target's Defense Value (DV)
  • Saving Throws: Roll vs. Effect DC

Advantage and Disadvantage

  • Advantage: Roll 2d20, take higher result
  • Disadvantage: Roll 2d20, take lower result
  • Multiple sources of advantage/disadvantage don't stack - you either have it or you don't

Critical Success and Failure

  • Natural 20: Critical success - double damage on attacks, automatic success on checks (DM discretion for impossible tasks)
  • Natural 1: Critical failure - automatic miss on attacks, automatic failure on checks with potential complication

Bounded Accuracy Framework

To maintain meaningful challenges across all levels, bonuses are intentionally limited:

Maximum Bonuses:

  • Attribute Modifier: +5 (20 attribute score)
  • Proficiency Bonus: +6 at level 20 (scales slowly)
  • Equipment Bonus: +3 (legendary gear only)
  • Total Maximum Bonus: +14 (core); +18 with mythic tier

Proficiency Bonus by Level:

Levels 1-4:   +2
Levels 5-8:   +3
Levels 9-12:  +4
Levels 13-16: +5
Levels 17-20: +6

Mythic Tier (Optional, Beyond Level 20):

Levels 21-24: +7
Levels 25-28: +8
Levels 29-30: +9

This keeps level 1 characters relevant in certain scenarios while allowing high-level characters to perform legendary feats without breaking the math.

Difficulty Classes

Standard DC Scale:

DC 5:   Trivial (nearly automatic)
DC 10:  Easy (trained individuals succeed regularly)
DC 15:  Moderate (requires focus and skill)
DC 20:  Hard (experts succeed more often than not)
DC 25:  Very Hard (only masters succeed reliably)
DC 30:  Near-Impossible (legendary difficulty)
DC 35+: Impossible for mortals (demigod+ only)

Contested Checks: When two characters oppose each other, both roll and highest total wins. Ties go to the defender/passive party.

Game Modes

Combat Mode

  • Structured turn order (initiative)
  • 6-second rounds
  • 3 actions + 1 reaction per turn
  • Precise positioning matters

Exploration Mode

  • Fluid time (minutes to hours)
  • Abstract movement
  • Group checks common
  • Environmental interaction focus

Downtime Mode

  • Measured in days/weeks
  • Training, crafting, research
  • Recovery and base-building
  • Narrative advancement