Foundational RPG Comparison Scaffold

Focus

This is a working scaffold for side-by-side comparison of foundational RPG chassis.

Baseline: B/X D&D (represented by Old-School Essentials) is the canonical reference point. All other systems are read against it. OSE faithfully restates the Moldvay/Cook 1981 B/X ruleset; where OSE adds optional rules not in original B/X (e.g., ascending AC, individual initiative), those are noted parenthetically.

Other columns include unique elements not present in B/X wherever they exist — the table does not force all systems into B/X categories.

The matrix is based on currently compiled system references and can be deepened further as additional editions and supplements are added.

How to Use This Table

Treat each row as one feature axis.
Read cells as implementation notes, not score judgments.
present means explicit support in core text.
light means present but sparse or referee-forward.
n/a means the subsystem is absent or not core-facing.

System Snapshot

Axis	B/X (OSE) ★	Shadowdark	Knave	Into the Odd	The Black Hack	Mork Borg	Troika!
Core stat model	Six stats (STR/INT/WIS/DEX/CON/CHA); 3d6 in order; score-band modifiers −3 to +3	Six stats (STR/DEX/CON/INT/WIS/CHA); 3d6 in order; unified modifier table −4 to +4	Six stats (STR/DEX/CON/INT/WIS/CHA)	Three stats (STR/DEX/WIL)	Six stats (STR/DEX/CON/INT/WIS/CHA)	Four stats (STR/AGI/PRE/TOU)	Core character numbers are Skill, Stamina, and Luck; Advanced Skills are background-derived
Character chassis	Seven classes — Cleric, Dwarf, Elf, Fighter, Halfling, Magic-User, Thief; demihumans are race-as-class; humans choose from four human classes	Ancestry + class split — 6 ancestries × 4 classes (Fighter/Priest/Thief/Wizard); 0-level funnel entry point	Classless, equipment-defined roles	Package-based starts, classless core	Four classes (Warrior/Thief/Cleric/Conjurer)	Optional classes plus classless default path	d66 background start with fixed possessions, Advanced Skills, and occasional Special rules
Task resolution	d20 vs THAC0/attack matrix for combat; five legacy save categories (death/wands/paralysis/breath/spells); informal ability checks (1-in-6 or 2-in-6 rolls, referee-facing)	d20 + stat modifier vs DC (Easy 9/Normal 12/Hard 15/Extreme 18); unified across all tasks; no legacy save categories	d20 + ability bonus vs target (typically >15)	d20 roll-under saves tied to STR/DEX/WIL	Universal d20 roll-under attribute tests	d20 + ability mod vs DR (commonly DR12)	2d6 Roll Under for unopposed tests and 2d6 Roll Versus for contests/combat
Durability	HP (d4–d8 by class), descending AC (9 = unarmored; lower = better); optional ascending AC (10 = unarmored; OSE addition)	HP (d4–d8 by class), ascending AC (10 unarmored; leather 11+DEX; chain 13+DEX; plate 15)	HP + armor defense/quality	HP then ability-score damage	HP + Armor Points (ablative)	HP + armor tiers + Broken/death pressure	Stamina as primary buffer; depleted stamina creates rapid collapse risk; armor mitigates hit effects
Magic model	Memorized spell slots per level (Cleric 1–5, Magic-User 1–6, Elf 1–5); Vancian preparation; Cleric Turn Undead; spell disruption on hit	Spells Known by tier (1–5) for Priest/Wizard; spellcasting check to cast; Wizard mishap table; Focus spells; Wizard can learn from scrolls	Spellbooks + large level-less spell list	Arcana-centric oddities and artifacts	Divine and Arcane spell slots with spell lists	Scrolls/powers + optional arcane catastrophes	Spell books and arcana with highly idiosyncratic effects; weirdness-forward over tactical spell taxonomy
Logistics model	Coin-weight encumbrance (items in coins; movement rate penalized by carried weight tiers)	Gear slots = STR stat (min 10); slot-based; no coin-weight tracking	Slot encumbrance central	Expedition gear pressure, lighter explicit slots	Usage die + item load threshold by STR	Carry limits + DR penalties + scarcity pressure	Inventory slots and unusual possessions drive problem-solving; travel pressure is procedural but lighter than strict turn economies

★ B/X column draws on OSE v1.4. OSE-specific optional rules noted parenthetically.

Procedure and Subsystem Matrix

Feature Axis	B/X (OSE) ★	Shadowdark	Knave	Into the Odd	The Black Hack	Mork Borg	Troika!
Initiative procedure	Group initiative each round (1d6 per side); optional individual DEX modifier (OSE addition)	Individual DEX check; highest goes first; turns proceed clockwise from winner for the encounter	Group initiative each round (d6)	Turn/action cadence, lighter formal initiative emphasis	Explicit turn structure with player-facing defense	Initiative d6 (group or individual variant)	Token stack: PCs add 2 tokens each, enemies add tokens by Initiative total, plus End of Round token
Save/test model detail	Five legacy categories (death/wands/paralysis/breath/spells) per class and level; no unified stat check	Unified stat check vs DC for all saves; no legacy categories; each threat maps to most relevant stat	Unified ability saves, opposed saves vs defenses	Save-or-consequence framing across STR/DEX/WIL	Attribute tests replace legacy save categories	DR test framework with ability mods	Unified 2d6 test model for skills/contests; fewer distinct save sub-systems
Player-facing combat option	Traditional — both sides roll attacks using THAC0 matrix; player looks up against target AC	Both sides roll d20 + stat vs AC using same framework; monsters and PCs treated symmetrically	Present (optional full player-facing mode)	Mostly player-facing via direct saves/attacks	Core identity: monsters rarely test to hit	Mixed, but strongly player-roll-centric in core checks	Mixed; players roll attacks and key checks, with referee adjudication for many effects
Armor handling	Flat descending AC (no ablation); optional ascending AC (OSE addition); armor passive defense only	Ascending AC fixed values; mithral removes stealth/swim penalties; no ablation or degradation	Armor defense plus quality degradation	Armor as reduction layer in concise model	Armor Points as ablative mitigation	Tiered armor reduction (light/medium/heavy)	Four armor tiers modify damage rolls by 0/-1/-2/-3 (minimum damage 1)
Critical/fumble pressure	1 always misses, 20 always hits; no expanded crit/fumble in core B/X	Natural 20 = critical hit (double damage dice or double one numerical spell effect); no fumble rule in core	Nat 1/20 effects include gear wear	Critical damage tied to ability loss and fallout	Nat 1/nat 20 combat effects + OofA consequences	Broken state and lethal fallout structure	Emphasis is on initiative volatility and consequence-forward rulings more than dedicated crit tables
Morale/reaction support	Present — Morale 2d6 vs morale score; Monster Reaction 2d6 table (CHA-modified); morale score 2–12 with edge cases	Present — Morale DC 15 WIS check at half numbers; no formal reaction table (GM interprets)	Present (2d6 reaction and morale procedure)	Present as referee procedure in encounter handling	Present (reaction table + encounter cadence)	Present (reaction 2d6 + morale 2d6)	Light in core; social outcomes are largely handled through fiction-forward adjudication
Resource depletion engine	Coin-weight encumbrance; Vancian spell slots (daily memorization); 10-minute dungeon turns drive resource expenditure cadence	Gear slots (STR-based); real-time torch tracking (1 torch = 1 hour real time); XP from treasure quality drives session pacing	Slots, gear quality, spellbook carry pressure	HP/ability damage + expedition consumables	Usage Die chain for consumables + armor fatigue	Omens, scarcity, carry penalties, misery pressure	12-slot inventory, stamina attrition, and explicit provision/rest recovery rules
Advancement procedure	Class-specific XP thresholds; prime requisite XP modifier (±10/20%); HD-based HP per level; THAC0 improves per level bracket; max level 10–14 by class	Level × 10 XP to advance; XP resets to 0; Talent rolls at odd levels; HP by class die per level; max level 10	Leveling with HP/ability growth choices	Leveling with HP and ability increase checks	Leveling with HD gain and stat-increase rolls	Advancement roll package (HP + ability checks)	Skill increases and stat growth tied to advancement checkpoints; background identity stays central
Bestiary compatibility	Native OSR HD/THAC0 framework; 200+ monsters in core; defines the OSR bestiary baseline	Monster Level (LV) system; native Shadowdark statblock format; not HD-first but readily convertible	Explicitly OSR/HD-compatible	Native odd-world statline model	HD-centered bestiary framework	Native statline model, not HD-first	OSR-adjacent conversion is feasible but requires tone and stat translation to fit surreal pacing

Included Tables and Generators (Granular)

Table/Generator Coverage	B/X (OSE) ★	Shadowdark	Knave	Into the Odd	The Black Hack	Mork Borg	Troika!
Character start package tables	present: class equipment lists with gp costs; starting wealth 3d6×10 gp; Retainer Hiring Reaction (2d6)	present: d12 random starting gear (0-level); 2d6×5 gp at 1st level; Crawling Kit contents table	present: starting gear table set (armor, helmets/shields, dungeoneering, general gear)	present: Starter Package Table with equipment/arcanum bundles	light: class-led starts + buy equipment economy	present: class/classless starts, silver rolls, starting kit tables	present: d66 Background table plus explicit baseline possessions and starting currency roll
Trait/background tables	n/a in core (3d6 stats in order only; no personality/trait tables)	present: Background table (d20 occupational backgrounds); Talent tables per class (2d6)	present: physique/face/skin/hair/clothing/virtue/vice/speech/background/alignment randomization	light: package identity and oddities; fewer explicit personality sub-tables in core player start	light: class profiles and advancement hooks	present: Terrible Traits, Broken Bodies, Bad Habits, Troubling Tales	present: Background entries include descriptive identity text, possessions, Advanced Skills, and optional Special clauses
Weapon/armor tables	present: full weapon stats (damage/cost/coins), armor table (AC values/cost/movement), adventuring gear price lists	present: Weapons table (15 entries: type/range/damage/properties); Armor table (4 entries with ascending AC formulas and properties)	present: weapon and gear stats integrated with slot load	present: weapon categories and armor entries in equipment lists	present: equipment catalog with prices and usage dice	present: weapons table, armor tiers, item pricing tables	present: concise weapon and armor lists; damage and armor interaction optimized for quick adjudication
Spell/arcana tables	present: Cleric spell lists levels 1–5 (~50 spells); Magic-User lists levels 1–6 (~100 spells); Elf subset; Turn Undead table	present: Priest Spells Known by tier/level; Wizard Spells Known by tier/level; Wizard Mishap table (d12); comprehensive spell reference by tier	present: 100 level-less spells list	present: random Arcana generation and example arcana sets	present: daily spell-slot tables + divine/arcane spell lists	present: Sacred/Unclean scroll tables (d10), arcane catastrophes (d20)	present: spell/arcana content oriented around bizarre utility and setting tone
Encounter tables	present: Dungeon Encounter tables by level (1–9), Wilderness Encounter tables by terrain type, wandering monster cadence rules	present: 25+ terrain-specific random encounter tables (arctic, cave, forest, jungle, ocean, ruins, swamp, tavern, tomb, urban districts, etc.)	light: supports random encounter procedure via OSR compatibility	present: encounter procedures plus setting encounter tables in referee material	present: random encounters (time-based trigger)	present: encounter procedures plus multiple adventure encounter tables	light: referee-guided encounter framing; fewer heavyweight encounter table stacks in core
Reaction/morale tables	present: Monster Reaction (2d6, CHA-modified); Morale check (2d6 vs morale score); morale score 2/12 special cases	light: Morale (DC 15 WIS check); no separate formal reaction table	present: reaction (2d6) and morale (2d6)	light: reaction procedure guidance, less formalized standalone charting	present: Creature Reactions table + morale handling	present: reaction (2d6) and morale (2d6)	light: mostly fiction-first social outcomes; morale style rulings are table-dependent
Injury/death fallout tables	light: death at 0 HP; no formal death-effects table in core B/X	present: Death Timer (1d4 + CON mod rounds to die); Stabilize check (DC 15 INT); natural 20 survival roll	light: death at -1 and gear break rules; limited dedicated injury charting	light: critical damage and ability collapse consequences	present: Out of Action aftermath table	present: Broken outcomes and lethal fallout structure	present: 0 Stamina during initiative becomes death at next End of Round token unless healed; below 0 is immediate death
Monster tables/bestiary	present: 200+ monsters with full HD/AC/THAC0/saves/movement/treasure type; Dungeon/Wilderness encounter tables	present: 80+ monsters by LV in Shadowdark statblock format; Monster Generator table (d20); Make It Weird table	light: conversion guidance for external OSR monsters	present: core monster examples and odd creature design support	present: monster HD damage table + monster list entries	present: monster entries + quick-reference stat/table pages	light: bestiary support exists but spotlight is on scenario weirdness and conversion-friendly rulings
World pressure/event tables	present: Treasure Types (A–V), Magic Item tables by category, Dungeon stocking tables, stronghold/domain construction outline	present: Something Happens! table, Rumors (d10), NPC/Rival Crawlers generators, Shadowdark Map generator, Overland Hex/Settlement Maps, Tavern/Shop tables, Treasure by tier, Boons	n/a in core	present in referee toolkit sections (district/world/event generators)	light: random encounter clock and referee-facing pacing tools	present: Misery engine (d66), Basilisks Demand (d20), adventure sparks (d100), corpse plundering (d66)	light: event pressure is usually imported from setting modules rather than core systemic engines
Name/faction/settlement generators	light: monster/NPC alignment and language guidance; limited named generators	present: Character Names (6 ancestries × d20); NPC personality tables; Rival Crawlers	light	present: name tables and broader city/faction-style generators in referee section	light	present: names, sparks, room/adventure support tables	light: strong character identity generation, lighter built-in faction/settlement generator depth

Coverage Notes

B/X (OSE) is the baseline. It defines the OSR HD/THAC0/descending-AC/five-save framework that all other columns react against or depart from.
Shadowdark is the most modern entry: unified DC resolution, ascending AC, real-time torch pressure, and talent-based customization while retaining OSR dungeon-crawl identity.
Into the Odd and Mork Borg have the highest visible generator density in currently ingested text.
Knave has strong character-facing table depth (traits, gear, spells) with lighter world-generator breadth.
The Black Hack concentrates on high-utility play tables for fast resolution (usage, encounters, reactions, HD damage, spell slots).
Troika! is OSR-adjacent with a surreal, fiction-forward cadence and highly distinctive initiative pressure.

Naming Row Interpretation (Design Use)

How to read Name/faction/settlement generators in the matrix: - present means a source includes first-class naming procedures usable at the table without importing external generators. - light means naming exists but is sparse, indirect, or mostly flavor support.

Friction implications for onboarding: - Strong character-name support (e.g., dedicated PC name tables) reduces chargen pause points. - Strong faction/settlement naming support reduces referee prep overhead between sessions. - Systems with light naming support benefit from a separate naming layer in onboarding docs.

Deep-Dive Notes by System

B/X (OSE)

The canonical OSR baseline. Defines the original race-as-class demihuman model, five-category save system, THAC0 combat matrix, Vancian memorization, and coin-weight encumbrance.
OSE adds: optional ascending AC, optional individual initiative, optional re-roll of low HP, high-level play guidance, and more explicit stronghold/domain rules — all clearly marked as optional.
Broadest monster bestiary of any system in this matrix (200+ entries); defines Treasure Types A–V as the loot-seeding standard.
Weakest on personality/trait generation (none in core) and world event generators (relies on dungeon stocking procedure rather than explicit random tables).

Shadowdark

Streamlined OSR descendant. Retains dungeon-crawl identity and HD-adjacency while replacing THAC0/saves with unified d20+stat vs DC.
Unique mechanics: real-time torch tracking as session clock; ancestry+class split (vs race-as-class); Talent rolls for incremental class customization; Wizard Mishaps as risk cost.
Strongest world-generator support of any system here: 25+ terrain-specific encounter tables, full GM toolkit for settlements/overland/dungeon procedural content.
No formal reaction table — a deviation from OSR tradition toward GM improvisation on social outcomes.

Knave

Strongest on classless clarity, inventory-defined role identity, and compatibility with external OSR material.
Table support is concentrated in character start, gear loadout, traits, and a large 100-spell list.
Procedural texture exists (reaction, morale, initiative), but world-generation table depth is lighter than Into the Odd and Mork Borg.

Into the Odd

Strongest on minimalist core resolution with heavy Arcanum-driven play identity.
Includes starter package support plus substantial referee-facing generation material in the text corpus (encounters, names, setting/event style tables).
Distinctive pressure model is HP-to-ability collapse rather than armor-attrition-first play.

The Black Hack

Strongest on streamlined table usability for play-at-speed: usage dice, random encounter cadence, reaction table, HD damage table, spell slot tables.
Class scaffolding is explicit and practical, with easy conversion from traditional OSR content.
Heavy support for player-facing resolution reduces GM roll overhead.

Mork Borg

Strongest on random table density and doom-pressure subsystems.
Includes broad table coverage across character generation, classes, omens, scrolls, catastrophes, miseries, encounters, and adventure sparks.
Emphasizes volatility and tone pressure as much as mechanical consistency.

Troika!

Character setup is explicit and compact: roll Skill (1d3+3), Stamina (2d6+12), Luck (1d6+6), record baseline possessions, then roll d66 background.
Core resolution is explicitly split between Roll Under and Roll Versus, with clear double-1 and double-6 behavior.
Initiative is token-stack based, including an End of Round token and optional enemy-token cap guidance.
Combat/damage procedures are tightly defined around Stamina loss, armor-based damage reduction, and End-of-Round death timing at 0 Stamina.