Dungeons & Dragons Rules Cyclopedia vs Old-School Essentials

Compare Dungeons & Dragons Rules Cyclopedia and Old-School Essentials side by side. See differences in complexity, dice, genre, and more.

	Dungeons & Dragons Rules Cyclopedia	Old-School Essentials
Genre	Fantasy	Fantasy
Tags	Classic Fantasy, Dungeon Crawl, Exploration, Hexcrawl, Random Tables, Vancian Casting, Descending AC, Base-Building, Domain Management, Crunchy	Dungeon Crawl, Exploration, Hexcrawl, Deadly, Sandbox, Resource Management, Inventory Management, Random Tables, Vancian Casting, Strong GM Support
Core Mechanic	Attacks roll 1d20 plus modifiers against a class-and-level target for the defender's Armor Class. Saving throws roll 1d20 against class-and-level targets. Ability checks roll 1d20 at or below the relevant ability score.	Attacks roll d20 against an attack matrix or an optional ascending Armour Class target. Saving throws meet a category target on d20. Ability checks roll at or below an ability score on d20.
Dice	d20	d20
Complexity	High	Low
Availability	Paid	Free core rules
Runnability	5 of 5 book tools	5 of 5 book tools
License	All Rights Reserved	OGL 1.0a
Third-Party Publishing	No verified route found	Commercial publishing allowed — Open license
Summary only, not legal advice. Check current terms before publishing.
Publisher	TSR, Inc.	Necrotic Gnome
Year	1991	2019
Languages	English, Japanese	English, Italian, Spanish, French, Czech, Portuguese, Chinese, Korean
Best For	Groups who want a classic fantasy campaign that grows from dangerous dungeon expeditions to managing a territory. It suits tables willing to learn additional procedures as the campaign expands.	Groups who want treasure-driven dungeon expeditions and open wilderness campaigns with fragile starting characters.
Highlights	Dungeon turn procedures make exploration a schedule of resource use and encounter checks. The War Machine resolves large battles without playing out every soldier's attack. Stronghold costs and dominion income give adventurers rules for becoming rulers.	Treasure recovered from adventures provides most experience points, rewarding successful exploration over fighting alone. Reaction and optional morale rolls let encounters lead to negotiation or flight instead of automatic combat. Stronghold construction and taxation let accumulated wealth support a growing domain.
Considerations	Dwarf, elf, and halfling classes normally have lower level caps than human classes. Starting ability scores are random, so a character may not qualify for a preferred class. Characters normally die at 0 hit points, making low-level encounters risky.	Characters die at zero hit points, and failed poison saves are usually fatal. Demihuman characters combine ancestry with class and have lower level limits than human classes. Declared spells are lost if the caster is hit or fails a saving throw before acting.